Wire harness, wire harness manufacturing method and wire harness manufacturing apparatus

ABSTRACT

A wire harness manufacturing method prevents inadvertent deformation of thermoplastic material and separation of thermoplastic material. A predetermined part of an electric wire  91  is accommodated in a through hole of a tubular body formed by connection between a first and second nest members ( 123, 124 ) of a nozzle ( 12 ), by integrally connecting first and second case body members ( 121, 122 ) of the nozzle ( 12 ), with the predetermined part of the electric wire  91  therebetween. An approximately tubular covering member ( 92 ) covering the predetermined part of the electric wire ( 91 ) is molded integrally with the thermoplastic material, by discharging thermoplastic material plasticized by a material plasticizing unit ( 11 ) from thermoplastic material discharge orifices ( 1213 ) and ( 1223 ) in the nozzle ( 12 ) to the outer periphery of the electric wire ( 91 ), while moving the electric wire ( 91 ) and the nozzle ( 12 ) relatively to each other.

CROSS-REFERENCE TO RELATED APPLICATIONS

This application is a divisional of U.S. patent application Ser. No.13/500,086 filed on Apr. 4, 2012.

BACKGROUND OF THE INVENTION

1. Field of the Invention

The present invention relates to a wire harness, a wire harnessmanufacturing method and a wire harness manufacturing apparatus, andmore particularly, to a wire harness in which a predetermined part ofelectric wire is provided with a member having a function of protectingthe electric wire and/or a function of bundling plural electric wires, amethod for manufacturing the wire harness, and an apparatus capable ofmanufacturing the wire harness (wire harness manufacturing apparatus).

2. Description of the Related Art

In a vehicle such as an automobile, a wire harness to mutually connectelectric devices and electronic devices is arranged. The wire harnessused for such application generally has predetermined types andpredetermined lengths of plural electric wires. These plural electricwires are bound (or bundled) in a predetermined form. Further,predetermined types of connectors and the like are attached to ends ofthe respective electric wires included in the wire harness. Then apredetermined part of the wire harness is provided with a member to bind(or bundle) an electric wire group not to unbind the respective electricwires and a member having a function of protecting the electric wire orelectric wire group.

As a structure to bind (or bundle) an electric wire group and protectthe electric wire(s), a structure to wrap a tape around thepredetermined part of an electric wire group, a structure to accommodatethe predetermined part of the electric wire group in a tube of resinmaterial or the like (e.g., a corrugate tube), a structure to embed thepredetermined part of the electric wire group in a molded resin member(insert molding), a structure to mold a member covering the outerperipheral surface of the predetermined part of the electric wire groupusing resin material, and the like, are used.

However, these structures may have the following problems.

When a tape is wrapped around the predetermined part of the electricwire group, in the tape-wrapped part, in comparison with the part beforethe wrapping (or an unwrapped part), the flexibility of the electricwire group (deformability of the electric wire group) is lowered.Accordingly, when the wire harness is arranged in a vehicle or the like,the handleability of the wire harness is lowered. This might reduceworking efficiency. In addition, the appearance of the tape-wrapped partis bad.

In the structure where the predetermined part of the electric wire groupis accommodated in a tube, the wire harness manufacturing apparatusand/or a manufacturing procedure is limited in accordance withstructures of connectors and the like. Generally, predeterminedconnectors and the like are attached to the ends of the electric wiresincluded in the wire harness. When the electric wires attached to theconnectors cannot be passed through the tube (e.g., when the sizes ofthe connectors and the like are larger than an inner diameter of thetube), it is necessary, as a procedure of the wire harnessmanufacturing, to first pass the predetermined part of the electric wiregroup through the tube (accommodate the part in the tube), then, attachthe connectors and the like to the ends of the electric wires. When anapparatus to automatically attach connectors and the like to the ends ofelectric wires may be used, however, when the electric wire group isaccommodated in the tube, it is impossible to set the electric wires insuch apparatus due to interference with the tube and/or the otherelectric wires in some cases. In this case, since it is impossible toautomatically attach the connectors and the like to the ends of theelectric wires, it is necessary to manually attach the connectors or thelike. It is difficult to reduce the manufacturing cost of the wireharness.

In the structure using a tube in which a slit is formed, it is necessaryto wrap a tape or the like around the outer peripheral surface of thetube to prevent falling of the electric wire or electric wire group.Since the number of process steps is increased, it is difficult toreduce the manufacturing cost. Further, the appearance of thetape-wrapped tube is bad.

Further, the tube used for the wire harness generally lacks apositioning mechanism with respect to the predetermined part of electricwire(s). Accordingly, it is necessary to wrap a tape or the like overthe electric wire group and the tube to prevent shift of the tube fromthe predetermined position of the electric wire group. Accordingly, itis difficult to reduce the number of process steps. Further, theappearance of the wrapped tape is bad.

In the structure where the predetermined part of the electric wire orelectric wire group is embedded in a molded part, a molding die(generally a die for injection molding) is required. It is necessary toprepare such molding die for parts in different lengths and diameters.Generally, since a molding die is expensive and is not very versatile,this structure using such molding die might increase the equipment cost.

In the structure to mold a resin part covering the predetermined part ofthe electric wire or electric wire group, a molding die corresponding tothe outer diameter (outer shape) of the electric wire or electric wiregroup is required. For a reason similar to that in the above structure,the structure might increase the equipment cost. Further, in thisstructure, it is difficult to change the thickness of the molded part.That is, in some cases, in the member covering the predetermined part ofthe electric wire or electric wire group, it is desirable to increasethe thickness of a part to have a function of protecting the electricwire or electric wire group while reducing the thickness of the otherpart. However, since the structure is approximately the same as astructure to mold a member to cover a core wire of an electric wire, itis difficult to change the thickness of the member.

In view of the above situation, the present invention has an object toprovide a wire harness in which, even when a covering member is molded,the reduction of flexibility (especially bendability) of the part inwhich the covering member is molded can be prevented or suppressed, amanufacturing apparatus of the wire harness and a method formanufacturing the wire harness. Further, the present invention hasanother object to provide a wire harness in which the covering member isnot shifted, a manufacturing apparatus of the wire harness and a methodfor manufacturing the wire harness. Further, the present invention hasanother object to provide a wire harness in which a good-appearancecovering member is molded, a manufacturing apparatus of the wire harnessand a method for manufacturing the wire harness. Further, the presentinvention has another object to provide a wire harness having anintegrally-formed covering member in which the thickness is changed, amanufacturing apparatus of the wire harness and a method formanufacturing the wire harness. Further, the present invention hasanother object to provide a wire harness capable of reducing equipmentcost and/or manufacturing cost or capable of preventing an increase inthe equipment cost and/or manufacturing cost, a manufacturing apparatusof the wire harness and a method for manufacturing the wire harness.

SUMMARY OF THE INVENTION

To achieve the objects and in accordance with the purpose of the presentinvention, a wire harness according to preferred embodiments of thepresent invention is prepared wherein a predetermined part of an outerperipheral surface of a single or a plurality of coated electric wires,in which a conductor is coated with a sheath member, is covered with acovering member formed by integrally molding with thermoplastic resinmaterial in an approximately tubular shape, wherein an inner peripheralsurface of the tubular-shaped covering member, which is plasticized bythermo plasticity of the thermoplastic material, is directly attached toa part of the outer peripheral surface of the electric wire positionedat the outside of the electric wire bundle, and wherein a gap is formedbetween the respective electric wires. A thickness of the tubular-shapedcovering member may be the same over an entire length in an axialdirection of the electric wire, or the thickness may be increased in amiddle position. It is possible that the thermoplastic resin materialforming the tubular-shaped covering member is polyester hot melt resin.

A wire harness manufacturing apparatus for manufacturing a wire harnesshaving an electric wire and a covering member, molded with thermoplasticmaterial, that covers a predetermined part of the electric wireaccording to the preferred embodiments of the present invention includesa material plasticizing unit that plasticizes the thermoplastic materialto a softened and plastic-deformable state upon reception of an externalforce, and a nozzle that has a through hole, integrally connectable andseparable into plural parts, which can accommodate the predeterminedpart of the electric wire when integrally connected, and a thermoplasticmaterial discharge orifice which continuously surrounds an outerperipheral surface of one end of the through hole, wherein, when thenozzle is integrally connected, the covering member that covers thepredetermined part of the electric wire can be integrally molded withthe thermoplastic material, by discharging the thermoplastic material,plasticized by the material plasticizing unit from the thermoplasticmaterial discharge orifice formed in the nozzle, on the outer peripheralsurface of the predetermined part of the electric wire projected fromone end of the through hole, in a state where the predetermined part ofthe electric wire is accommodated in the through hole formed in thenozzle.

It is possible that the nozzle has a plurality of nest members mutuallyintegrally connectable and separable that, in the connected state, forma tubular body in which the rough hole is formed, and a plurality ofcase members, mutually integrally connectable and separable, in whichthe plurality of nest members can be fitted, wherein when the pluralityof case members in which the plurality of nest members are fitted areconnected, the plurality of nest members are also connected to form thetubular body, and the through hole in the tubular body formed byconnection of the plurality of nest members becomes a through hole thataccommodates the predetermined part of the electric wire, and whereinthe thermoplastic material discharge orifice is formed on the outerperipheral surface of one end of the tubular body in an axial directionformed by connection of the plurality of nest members.

It is possible that in each of the plurality of nest members, agroove-shaped thermoplastic material channel is formed in a surfacewhich becomes an outer peripheral surface of the tubular body when theplurality of nest members are connected to form the tubular body, andwherein the plasticized resin material is discharged from thethermoplastic material discharge orifice through the groove-shapedthermoplastic material channel.

It is possible that the nozzle has a plurality of tabular membersmutually integrally connectable and separable that, in the connectedstate, form a tabular body in which the through hole is formed, whereinthe through hole of the tabular body formed by connection between theplurality of tabular members becomes the through hole that accommodatesthe predetermined part of the electric wire, and wherein thethermoplastic material discharge orifice is formed in an outer peripheryof one end of the through hole in the axial direction in the tabularbody formed by connection of the plurality of tabular members.

It is possible that in each of the plurality of tabular members, thegroove-shaped thermoplastic material channel, capped with a lid member,is formed in a planar direction of the tabular body, and wherein theplasticized resin material is discharged from the thermoplastic materialdischarge orifice through the groove-shaped thermoplastic materialchannel.

It is possible that a plurality of groove-shaped thermoplastic materialchannels is formed, and a channel cross-sectional area is increased inaccordance with increment in channel length to the discharge orifice.

It is preferable that the wire harness manufacturing apparatus accordingto the preferred embodiments of the present invention further includesan air blowing unit that cools down the covering member molded with thethermoplastic material discharged from the thermoplastic materialdischarge orifice of the nozzle by sending air to the covering member.

A wire harness manufacturing method according to the preferredembodiments of the present invention includes steps of covering an outerperiphery of a predetermined part of a single wire or a bundle of aplurality of electric wires, in which a conductor is coated with asheath member, with a covering member, formed by integral molding in anapproximate tubular shape, by heating thermoplastic resin material to atemperature at which the thermoplastic resin is plastic-deformable andwhich is lower than a fusing point and discharging the thermoplasticresin material to the outer periphery of the predetermined part from aplurality of directions in a circumferential direction, directlyattaching an inner peripheral surface of the tubular-shaped coveringmember to a part of an outer peripheral surface of the electric wirepositioned outside the bundle of electric wires, and forming a gapbetween the respective electric wires. It is possible that in formationof the tubular shaped covering member by discharging the thermoplasticresin material to the outer periphery of the bundle of electric wires,the bundle of electric wires is relatively moved in an axial directionof the bundle of electric wires with respect to a discharge part of thethermoplastic resin material. Further, it is possible that a thicknessof the tubular-shaped covering member is made to be uniform over anentire length or changed in a middle position in the axial direction ofthe electric wire by controlling a discharge amount of the thermoplasticresin material per unit time or a speed of relative movement of thebundle of electric wires in the axial direction. In addition, it ispossible that the thermoplastic resin material forming thetubular-shaped covering member is polyester hot melt resin.

The wire harness manufacturing method according to the preferredembodiments of the present invention using the wire harnessmanufacturing apparatus according to the invention includes steps ofaccommodating the predetermined part of the electric wire in the throughhole by integrally connecting the nozzle while holding the predeterminedpart of the electric wire inside, and integrally molding the coveringmember in the approximate tubular shape covering the predetermined partof the electric wire with the thermoplastic material by discharging thethermoplastic material plasticized by the material plasticizing unitfrom the thermoplastic material discharge orifice of the nozzle to theouter periphery of the predetermined part of the electric wire whilemoving the predetermined part of the electric wire and the nozzlerelatively to each other.

It is possible that the thickness of the covering member is controlledby controlling the speed of relative movement between the predeterminedpart of the electric wire and the nozzle and/or the amount of thethermoplastic material discharged from the thermoplastic materialdischarge orifice of the nozzle per unit time.

It is possible that in the wire harness manufacturing method, thecovering member in the approximate tubular shape covering thepredetermined part of the electric wire is integrally molded with thethermoplastic material by discharging the thermoplastic materialplasticized by the material plasticizing unit to the outer periphery ofthe predetermined part of the electric wire, and the inner peripheralsurface of the covering member and the outer periphery of thepredetermined part of the electric wire are attached by plasticity ofthe thermoplastic material.

The wire harness manufacturing method according to the preferredembodiments of the present invention using the wire harnessmanufacturing apparatus according to the invention includes steps ofmolding a covering member of thermoplastic material in the predeterminedpart of the electric wire by the wire harness manufacturing methodaccording to any one of the above-mentioned method, stopping relativemovement between the predetermined part of the electric wire and thenozzle and cooling down the molded covering member by sending air to thecovering member from the air blowing unit, and thereafter, cutting themolded covering member and the thermoplastic material existing in thenozzle in a position of the thermoplastic material discharge orifice ofthe nozzle and separating the covering member from the thermoplasticmaterial, by moving the predetermined part of the electric wire and thenozzle relatively to each other without discharging the thermoplasticmaterial from the thermoplastic material discharge orifice of thenozzle.

In the wire harness according to the present invention, the reduction ofthe flexibility of a part in which the covering member is molded can beprevented or suppressed. Accordingly, when the wire harness according tothe present invention is arranged inside a vehicle or the like, sincethe predetermined part can be easily deformed, the working efficiency ofthe arranging can be improved.

As the inner peripheral surface of the covering member is attached tothe predetermined part of the electric wire, the covering member is notmoved from the predetermined part of the electric wire. Accordingly, nostructure or working step to prevent movement of the covering member isnecessary. It is possible to reduce the manufacturing cost and thenumber of process steps.

Further, the appearance of the wire harness is good in comparison with astructure where a tape as a covering member is wrapped around theelectric wire.

In the wire harness manufacturing apparatus according to the presentinvention, it is possible to prevent or suppress the rise of equipmentcost or reduce the equipment cost.

That is, for example, the nozzle applied to the wire harnessmanufacturing apparatus according to the present invention has a simplestructure and is manufactured at a low cost in comparison with aninjection mold die. That is, the injection mold die requires a structureto resist pressure of injected thermoplastic material. On the otherhand, since no high pressure is applied to the nozzle used the wireharness manufacturing apparatus according to the present invention, thestructure to resist high pressure is not required. Accordingly, thenozzle has a simple structure and can be manufactured in a small size.

Further, in general injection molding, a mold clamping mechanism isrequired so as not to separate upper and lower molds of the molding diedue to the pressure of the injected thermoplastic material. Accordingly,the structure of equipment to form the covering member is complicatedand is expensive. On the other hand, in the wire harness manufacturingapparatus according to the present invention, even while thermoplasticmaterial is discharged, no force to separate integrally-connected pluralcasing members is applied. Accordingly, the wire harness manufacturingapparatus according to the present invention does not require amechanism corresponding to the mold clamping mechanism in the equipmentfor injection molding.

Further, in general injection molding, it is necessary to apply highpressure to the thermoplastic material to fill thermoplastic material ina mold die. On the other hand, in the structure of the wire harnessmanufacturing apparatus according to the present invention, it issufficient to merely apply pressure to the plasticized resin material ata level to discharge (flow) the resin material from a discharge orificeof the nozzle. Accordingly, in comparison with the injection molding,since the pressure applied to the thermoplastic material is low, a smallsized device is applicable as a device to feed the thermoplasticmaterial. Further, a thermoplastic material channel (hose or the likeconnecting a material plasticizing unit with the nozzle) does notrequire a structure to resist high pressure.

Further, the wire harness manufacturing apparatus according to thepresent invention has high versatility.

For example, in the structure to form a covering member by injectionmolding, only one type (one size and one shape) of covering member ismolded with a set of mold dies. Accordingly, to form a covering memberin which the thickness changes, it is necessary to prepare mold dies forrespective thicknesses of the covering member. Similarly, to form acovering member in which the axial directional length changes, it isnecessary to prepare mold dies for respective axial directional lengthsof the covering member. On the other hand, the nozzle applied to thewire harness manufacturing apparatus according to the present inventioncan change the thickness of the covering member by controlling the speedof relative movement of the nozzle with respect to a predetermined partof the electric wire and/or controlling the discharge amount of thethermoplastic material per unit time. Accordingly, it is possible with apair of nozzles to form a covering member in which the thicknesschanges. Further, it is possible to form a covering member in anappropriate length in the predetermined part of the electric wire byappropriately setting a range of relative movement of the nozzle withrespect to the predetermined part of the electric wire.

Further, when the predetermined part of the electric wire has a size tobe accommodated in a through hole formed with connected plural nestmembers, the covering member can be molded regardless of the outerdiameter of the predetermined part of the electric wire. Accordingly, itis possible to handle the plural sizes of the electric wire (when pluralelectric wires are included, the diameter of the electric wire bunch)with the pair of nozzles. Further, even when the diameter of theelectric wire changes in the middle of the axial direction, it ispossible to integrally mold the covering member over the diameter-changepart without discontinuity (or without nozzle change).

Further, as long as the thermoplastic material channel is formed in aplanar direction of a tabular plane formed by connection between a firsttabular member and a second tabular member, the thickness of the nozzle(size in the axial direction of the electric wire) can be reduced.Accordingly, the covering member can be formed to a position closer tothe root (branch point or the like) of the electric wire.

Further, when plural thermoplastic material channels are formed and along channel has a large cross-sectional area, pressure loss due to lineresistances in the respective channels can be approximately uniform.That is, since it is possible to approximately obtain a state as thepressure of the thermoplastic material discharged from the dischargeorifice of the nozzle is uniform in a circumferential direction of theelectric wire, the thickness of the formed covering member is uniform inthe circumferential direction.

In the wire harness manufacturing method according to the presentinvention, the order of the step of attaching a connector or the like tothe end of the electric wire and the step of molding the covering memberin the predetermined part of the electric wire is not limited.Accordingly, in the wire harness manufacturing method according to thepresent invention, it is possible to attach predetermined connectors andthe like to the ends of the respective electric wires then bundle theelectric wires, and mold the covering member. Accordingly, the step ofattaching the connectors and the like to the ends of the electric wiresis performed in a state where each electric wire individually exists.Accordingly, at the step of attaching the connectors and the like usinga device to automatically attach the connectors and the like, there isno difficulty in setting of the connectors and the like due tointerference with other electric wires or covering member. It istherefore possible to perform the step of attaching the connectors andthe like to the respective electric wires using the device toautomatically attach the connector and the like, and reduce themanufacturing cost.

Further, in the wire harness manufacturing method according toembodiments of the present invention, it is possible to mold a coveringmember 92 in which the thickness changes along an axial direction (i.e.,a covering member in which the strength changes) simply and integrally.More particularly, during molding of the covering member, the thicknessof the covering member can be adjusted only by controlling the speed ofrelative movement of the nozzle with respect to a predetermined part ofthe electric wire and/or the amount of thermoplastic material dischargedfrom the discharge orifice of the nozzle per unit time. That is, it ispossible to integrally mold the covering member in which the thicknesschanges along the axial direction. Accordingly, as it is not necessaryto provide plural covering members, it is possible to reduce the numberof process steps. Further, since it is possible to integrally mold thecovering member in which the thickness changes along the axial directionwith the thermoplastic material, it is possible to reduce the number ofparts of the wire harness.

In the wire harness manufacturing method according to the embodiments ofthe present invention, it is possible to cut the molded covering memberat its terminal end without causing plastic deformation of the coveringmember by pulling it out. Accordingly, the appearance of the coveringmember in the axial direction can be improved.

When an air blowing unit sends air to the molded covering member, thecovering member is quickly cooled down. Accordingly, plastic deformationby thermal plasticity does not occur in the covering member. On theother hand, since the thermoplastic material existing in the nozzle doesnot receive air sent from the air blowing unit and is not cooled,plastic deformation by thermal plasticity easily occurs. As a result, aborder between a part in which the plastic deformation by thermalplasticity does not occur and a part in which the plastic deformation bythermal plasticity easily occurs, is formed in thermoplastic material(including the formed covering member) in the position of the dischargeorifice of the nozzle.

In this state, when the nozzle and the predetermined part of theelectric wire are relatively moved, the thermoplastic material existingin the nozzle remains in the nozzle by a friction force or the like. Onthe other hand, in the part (molded covering member) of thethermoplastic material discharged from the discharge orifice of thenozzle, plastic deformation by thermo plasticity does not occur,therefore it is not plastic-deformed even when a pulling force in theaxial direction is applied. Accordingly, at the thermoplastic materialdischarge orifice of the nozzle (i.e., on the border between thethermoplastic-deformable part and the undeformable part), it is possibleto cut the molded covering member and the thermoplastic material beforemolding without causing plastic deformation by pulling out therespective parts.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1A is an external perspective diagram of a predetermined part (apart in which a cover member is provided) of a wire harness according toembodiments of the present invention;

FIG. 1B is a cross-sectional diagram along a line A-A in FIG. 1Aschematically showing a cross-sectional structure of the predeterminedpart of the wire harness according to the embodiments of the presentinvention;

FIG. 2 is an external perspective diagram of the predetermined part ofthe wire harness according to the embodiments of the present invention,in which the thickness of the covering member changes along an axialdirection;

FIG. 3 is a schematic diagram showing principal elements in thestructure of a wire harness manufacturing apparatus according to a firstembodiment of the present invention;

FIG. 4 is an exploded external perspective diagram schematically showingthe structures of respective elements of a nozzle of the wire harnessmanufacturing apparatus according to the first embodiment of the presentinvention;

FIG. 5 is an external perspective diagram of the nozzle built in thewire harness manufacturing apparatus according to the first embodimentof the present invention showing a state where a first case body memberand a second case body member are separated;

FIG. 6 is an external perspective diagram of the nozzle built in thewire harness manufacturing apparatus according to the first embodimentof the present invention showing a state where the first case bodymember and the second case body member are connected;

FIG. 7A is a schematic diagram showing the structure of thermoplasticmaterial channels respectively formed in a first nest member and asecond nest member of the wire harness manufacturing apparatus accordingto the first embodiment of the present invention, viewed from one end ofthe axial direction;

FIG. 7B is a plane diagram showing the thermoplastic material channelsformed in the respective outer peripheral surfaces of the first nestmember and the second nest member;

FIG. 7C is a cross-sectional diagram along a line A-A in FIG. 7B;

FIG. 7D is a cross-sectional diagram along a line B-B in FIG. 7B;

FIG. 8 is a perspective diagram schematically showing the structures ofthe principal elements of the wire harness manufacturing apparatusaccording to a second embodiment of the present invention;

FIG. 9 is an exploded external perspective diagram showing thestructures of respective elements in the nozzle of the wire harnessmanufacturing apparatus according to the second embodiment of thepresent invention;

FIG. 10 is a cross-sectional diagram along a line C-C in FIG. 9;

FIG. 11 is an external perspective diagram showing the nozzle built inthe wire harness manufacturing apparatus according to the secondembodiment of the present invention showing a state where a firsttabular member and a second tabular member are separated;

FIG. 12A is a plane diagram showing the structure of the thermoplasticmaterial channels formed in the first tabular member (second tabularmember) of the wire harness manufacturing apparatus according to thesecond embodiment of the present invention;

FIG. 12B is a side diagram of the first tabular member (second tabularmember);

FIG. 13 is a cross-sectional diagram along a line D-D in FIG. 12A in astate where a lid member is fixed;

FIG. 14 is a perspective diagram schematically showing a step of forminga covering member;

FIG. 15 is a perspective diagram schematically showing another step offorming the covering member;

FIG. 16 is a perspective diagram schematically showing another step offorming the covering member;

FIG. 17 is a perspective diagram schematically showing another step offorming the covering member; and

FIGS. 18A and 18B are schematic diagrams for explaining advantages ofthe wire harness manufacturing apparatus according to the secondembodiment of the present invention.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

Hereinbelow, preferred embodiments of the present invention will bedescribed in detail with reference to the drawings.

FIGS. 1A and 1B show a predetermined part (a part in which a coveringmember 92 is provided) of a wire harness 9 according to the embodimentsof the present invention. More particularly, FIG. 1A is an externalperspective diagram of the predetermined part of the wire harness 9according to the embodiments of the present invention. FIG. 1B is across-sectional diagram along a line A-A in FIG. 1A, schematicallyshowing a cross-sectional structure of the predetermined part of thewire harness 9 according to the embodiments of the present invention.

The wire harness 9 according to the embodiments of the present inventionhas plural electric wires 91 in a predetermined length and of apredetermined type. The predetermined number of electric wires 91 arebundled to a predetermined shape as a whole (so as to form apredetermined trunk line or a predetermined branch line). That is, asingle electric wire 91 or bundled plural electric wires 91 form apredetermined trunk line or a predetermined branch line in the wireharness 9 according to the embodiments of the present invention.Further, predetermined connectors and the like (not shown) are attachedto ends of the respective electric wires. Note that the entire shape andsize of the wire harness 9 according to the embodiments of the presentinvention, and the number, and the type of the electric wires 91included in the wire harness 9 according to the embodiments of thepresent invention, and the connectors and the like attached to the endsof the respective electric wires 91, are not particularly limited butappropriately set.

As shown in FIGS. 1A and 1B, the predetermined part of the wire harness9 according to the embodiments of the present invention has a single orplural electric wires 91, and the covering member 92 to cover a singleelectric wire 91 or the covering member 92 to cover plural electricwires 91 is provided in this part. The covering member 92 has a functionof binding plural electric wires 91 (to bundle plural electric wires 91so as not to unbind them) and a function as a protector to guard theelectric wire/wires 91. Note that in FIG. 1, the predetermined part ofthe wire harness 9 according to the embodiments of the present inventionhas plural electric wires 91 while it may have a single electric wire91. The number of the electric wires 91 in the predetermined part of thewire harness 9 according to the embodiments of the present invention isnot particularly limited. Further, in the present invention, the“electric wire” 91 has a meaning of single electric wire and a meaningof plural electric wires unless it is specifically defined.

The covering member 92 is a member molded in an approximate tubularshape having a hollow inside, which is formed so as to cover the outerperipheral surface of the electric wires 91 (in other words, it isformed so as to accommodate the electric wires 91 inside). The coveringmember 92 is easily deformable (as the deformation is not the plasticdeformation, the original shape can be restored) with human force.Further, the covering member 92 is not easily plastic-deformed at anenvironmental temperature when the use of the wire harness 9 accordingto the embodiments of the present invention is presumed.

In the covering member 92, a part of its inner peripheral surface isattached to the electric wire 91. When the predetermined part of thewire harness 9 according to the embodiments of the present inventionincludes plural electric wires 91, the part of the inner peripheralsurface of the covering member 92 is attached to some or all the pluralelectric wires 91. The covering member 92 is molded so as to cover theouter periphery of the electric wires 91 included in the predeterminedpart of the wire harness 9 according to the embodiments of the presentinvention. Accordingly, as long as a single or a small number ofelectric wires 91 (two to four, the number differs in accordance withthe form of the bundled electric wires 91) are included in thepredetermined part, a part of the outer peripheral surfaces all theelectric wires 91 is in contact with the inner peripheral surface of thecovering member 92, thus all the electric wires 91 are attached to theinner peripheral surface of the covering member 92.

Note that when a large number of electric wires 91 are included in thepredetermined part, when these many electric wires 91 are bundled (abunch of electric wires 91), an electric wire 91 surrounded by otherelectric wires 91 and not exposed to the outside of the bundle of theelectric wires 91 may exist. Such electric wire 91, not in contact withthe inner peripheral surface of the covering member 92, is not attachedto the covering member. In other words, among the bundled electric wires91, a part of an exposed part (not a part facing other electric wires91) in the outer peripheral surface positioned in the outermost side isattached to the inner peripheral surface of the covering member 92. Inthis manner, a part of the inner peripheral surface of the coveringmember 92 is attached to the electric wires 91. However, the part of theinner peripheral surface of the covering member 92 is not alwaysattached to all the electric wires 91.

The covering member 92, of thermoplastic material, is molded byutilizing thermo plasticity of the thermoplastic material. The coveringmember 92 is integrally molded using the thermoplastic material, but notmolded by combining (joining) plural parts, and no “seam” or the like ofthe thermoplastic material is formed in the covering member 92. As thethermoplastic material, various thermoplastic resin materials areapplicable. For example, polyester hot melt resin is applicable.

The thickness of the covering member 92 is not particularly limited butit is appropriately set in correspondence with function and the level ofthe function to be provided in the covering member 92. For example, whenthe covering member 92 is provided with the function as a protector toguard the electric wire 91, the thickness of the covering member 92 isincreased to have high strength not to damage the electric wire 91. Onthe other hand, when the covering member 92 is provided with only thefunction of holding the electric wires, the covering member has athickness merely to obtain sufficient strength to bundle the electricwires. In this way, the thickness of the covering member 92 can beappropriately set.

FIG. 2 is an external perspective diagram of the predetermined part ofthe wire harness 9 according to the embodiments of the presentinvention, in which the thickness of the covering member 92 is changedalong the axial direction. As shown in FIG. 1, the covering member 92may have a thickness approximately uniform over the entire length alongthe axial direction, or may have a thickness which changes along theaxial direction. For example, in the covering member molded in thepredetermined part of the wire harness according to the embodiments ofthe present invention, the thickness in a position where protection ofthe electric wire is to be enhanced can be increased. Further, thethickness of the covering member 92 may be different in accordance withrequired level of protection for the electric wire 91. In this way, thethickness of the covering member 92 is appropriately set incorrespondence with function or the like required of the coveringmember.

Note that the covering member 92 having a thickness approximatelyuniform over the entire length in the axial direction and the coveringmember 92 having a thickness which changes along the axial direction areintegrally molded using thermoplastic material. That is, for example, inthe covering member having a thickness which changes along the axialdirection, in place of a structure where another part is attached to athin part to increase the thickness or a structure where tubular-shapedmembers having different thicknesses are connected along the axialdirection, a structure where a thick part and a thin part are integrallymolded as a whole.

Next, a wire harness manufacturing apparatus 1 according to a firstembodiment of the present invention will be described.

FIG. 3 is a schematic diagram showing principal elements in thestructure of the wire harness manufacturing apparatus 1 according to thefirst embodiment of the present invention. As shown in FIG. 3, the wireharness manufacturing apparatus 1 according to the first embodiment ofthe present invention has a material plasticizing unit 11, a nozzle 12,and an air blowing unit 13. The wire harness manufacturing apparatus 1according to the first embodiment of the present invention molds thecovering member 92 so as to cover the electric wire 91 byheat-plasticizing thermoplastic material as the material of the coveringmember by the material plasticizing unit 11 and feeding the materialthrough a hose (member as a channel of the thermoplastic material) 14 orthe like to the nozzle 12, and discharging the plasticized thermoplasticmaterial from the nozzle 12. Further, the air blowing unit 13 cools downthe thermoplastic material discharged from the nozzle 12 (moldedcovering member 92) by sending air to the material.

In this manner, in manufacture of the wire harness 9 according to theembodiments of the present invention, the wire harness manufacturingapparatus 1 according to the first embodiment of the present inventionmolds the covering member in a predetermined part of the electric wire91 in the wire harness 9 according to the embodiments of the presentinvention. Accordingly, it is also a “wire harness (or electric wire)covering member molding apparatus”.

The material plasticizing unit 11 is a tool to heat and plasticize thethermoplastic material the material, and feed the plasticized materialto the nozzle 12. Conventionally, various material plasticizing unitsare applicable as the material plasticizing unit 11. For example, aknown general heating device used in resin material injection molding toheat and plasticize resin material is applicable. Accordingly, theexplanation of the material plasticizing unit 11 will be omitted.

The heating temperature to heat the thermoplastic material by thematerial plasticizing unit 11 is set to a temperature at which thethermoplastic material is in a plastically-deformable state (fluidalstate, gel state) and the plasticized thermoplastic materials, when incontact, are connected and integrated. Note that at that temperature,the material is plastically deformable by thermo plasticity, and thetemperature is lower than a fusing point and lower than a heatingtemperature (particularly a temperature recommended by thermoplasticmaterial makers) in general molding process (e.g., general injectionmolding or press molding) for the thermoplastic material. For example, atemperature around a lower limit of a temperature range in which thethermoplastic material is plastically deformable by thermo plasticity.

When polyester hot melt resin is applied as the thermoplastic material,as the temperature of heating by the material plasticizing unit, atemperature within the range of 110° C. to 150° C. is applied. Thefusing point of the polyester hot melt resin is about 190° C. In generalinjection molding, the polyester hot melt resin is heated to 190° C. to210° C.

The nozzle 12 is a tool to mold the covering member 92 by dischargingthe thermoplastic material plasticized by the material plasticizing unit11 so as to cover the periphery of the electric wire 91 in the wireharness 9. FIG. 4 is an exploded external perspective diagramschematically showing respective elements in the structure of a nozzle12. FIGS. 5 and 6 are external perspective diagrams of the built nozzle12. FIG. 5 shows a state where a first case body member 121 and a secondcase body member 122 are separated. FIG. 6 shows a state where the firstcase body member 121 and the second case body member 122 are connected.

As shown in FIG. 4, the nozzle 12 has the first case body member 121,the second case body member 122, a first nest member 123 and a secondnest member 124. As shown in respective FIGS. 5 and 6, the first nestmember 123 is fitted in the first case body member 121, and the secondnest member 124 is fitted in the second case body member 122. The firstcase body member 121 in which the first nest member 123 is fitted andthe second case body member 122 in which the second nest member 124 isfitted can be separably connected. In the first case body member 121 inwhich the first nest member 123 is fitted and the second case bodymember 122 in which the second nest member 124 is fitted, thermoplasticmaterial discharge orifices (hereinbelow, simply referred to as“discharge orifices”) 1213 and 1223 are formed. When the first case bodymember 121 in which the first nest member 123 is fitted and the secondcase body member 122 in which the second nest member 124 is fitted areconnected, the discharge orifices 1213 and 1223 are integrated. Theapproximately tubular-shaped covering member 92 is formed by dischargingthe plasticized thermoplastic material from the discharge orifices 1213and 1223.

The first nest member 123 and the second nest member 124 can beseparably connected. When the first nest member 123 and the second nestmember 124 are connected, one tubular body (a structure having apredetermined length in the axial direction and a through hole formedfrom one end to the other end in the axial direction) is constituted.The first nest member 123 and the second nest member 124 have structuresas if they are obtained by dividing a tubular body into halves along theaxial direction.

The first nest member 123 and the second nest member 124 are connected,with the electric wire 91 included in the predetermined part of the wireharness 9 according to the embodiments of the present invention,therebetween. That is, the tubular body formed by the connection betweenthe first nest member 123 and the second nest member 124 accommodates(in other words, the electric wire 91 can be inserted through) theelectric wire 91 included in the predetermined part of the wire harness9 according to the embodiments of the present invention. In a statewhere the electric wire 91 included in the predetermined part of thewire harness 9 according to the embodiments of the present invention isaccommodated in the through hole of the tubular body formed by theconnection between the first nest member 123 and the second nest member124, the tubular body formed by the connection between the first nestmember 123 and the second nest member 124 and the electric wire 91included in the predetermined part of the wire harness 9 according tothe embodiments of the present invention can relatively move along theiraxial direction.

Accordingly, the through hole of the tubular body formed by theconnection between the first nest member 123 and the second nest member124 has a shape and a size to accommodate the electric wire 91 includedin the predetermined part of the wire harness 9 according to theembodiments of the present invention. Further, the cross-sectional sizeand shape of the tubular body formed by the connection between the firstnest member 123 and the second nest member 124 define thecross-sectional size and shape of the covering member 92. Further, whenplural electric wires 91 are included in the predetermined part of thewire harness 9 according to the embodiments of the present invention,the cross-sectional size and shape of the tubular body define thecross-sectional shape of a bundle of electric wires 91. When thecross-sectional shape of the covering member 92 is an approximatecircular shape and plural electric wires 91 are bundled so as to have anapproximately circular cross-sectional shape, the cross-sectional shapeof the tubular body formed by the connection between the first nestmember 123 and the second nest member 124 is an approximate circularshape. In this case, the first nest member 123 and the second nestmember 124 are respectively a member having an approximately circularcross-sectional shape and a predetermined length.

Note that in the present embodiment, the cross-sectional shape of thetubular body formed by the connection between the first nest member 123and the second nest member 124 is an approximately circular shape.However, the cross-sectional shape of the tubular body is notparticularly limited. For example, it may be a polygonal shape such as arectangular shape. That is, it is appropriately set in correspondencewith the cross-sectional shape of the covering member 92 and thecross-sectional shape of the bundled electric wires 91.

The shape of the outer peripheral surface of the tubular body formed bythe connection between the first nest member 123 and the second nestmember 124 is not particularly limited. For example, as shown inrespective FIGS. 4 to 6, it may be formed to approximately the samecross-sectional shape to the cross-sectional shape of the through hole(approximately circular shape in the present embodiment) or to anothershape. That is, it may be arranged such that the cross-sectional shapeof the tubular body formed by the connection between the first nestmember 123 and the second nest member 124 is an approximately circularshape and the cross-sectional shape of the outer peripheral surface is apolygonal shape (rectangular shape, hexagonal shape or the like).

Note that thermoplastic material channels 1231 and 1241 are formed inthe outer peripheral surface of the tubular body formed by theconnection between the first nest member 123 and the second nest member124. The end points of the thermoplastic material channels 1231 and 1241are formed at one end of the tubular body in the axial direction and inthe vicinity of the inner peripheral surface of the through hole (in aposition closest to the outside of the through hole) (to be describedlater). Accordingly, it is preferable that the cross-sectional shape ofthe outer peripheral surface of the tubular body formed by theconnection between the first nest member 123 and the second nest member124 is approximately the same as the cross-sectional shape of thethrough hole. That is, the cross-sectional shape of the tubular bodyformed by the connection between the first nest member 123 and thesecond nest member 124 has an approximately uniform thickness over theentire periphery in the circumferential direction.

A part around one end of the tubular body formed by the connectionbetween the first nest member 123 and the second nest member 124 in theaxial direction is formed to a thin-nose shape in which thecross-sectional size is gradually reduced toward the one end in theaxial direction. For example, when the cross-sectional shape of theouter peripheral surface of the tubular body formed by the connectionbetween the first nest member 123 and the second nest member 124 is anapproximate circular shape, the part around the one end in the axialdirection is formed to a shape like a sliced piece cut from a conethinned toward the end.

In the first nest member 123 and the second nest member 124, thethermoplastic material channels 1231 and 1241 are formed. FIGS. 7A to 7Dshow the structure of the thermoplastic material channels 1231 and 1241formed in the respective first nest member 123 and the second nestmember 124. More particularly, FIG. 7A is a schematic diagram showingthe structure of the first nest member 123 and the second nest member124, viewed from one end of the axial direction. FIG. 7B is a planediagram of the (thermoplastic material channels 1231 and 1241 formed in)the respective outer peripheral surfaces of the first nest member andthe second nest member. FIG. 7C is a cross-sectional diagram along aline A-A in FIG. 7B. FIG. 7D is a cross-sectional diagram along a lineB-B in FIG. 7B.

As shown in FIGS. 7A to 7D, the thermoplastic material channels 1231 and1241 are grooves formed in the respective outer peripheral surfaces ofthe first nest member 123 and the second nest member 124. Asparticularly shown in FIG. 7B, in the respective outer peripheralsurfaces of the first nest member 123 and the second nest member 124,the thermoplastic material channels 1231 and 1241 have a predeterminedposition in the middle in the axial direction as a start point and theone end in the axial direction as an end point (arrive at one end in theaxial direction). In other words, the one ends of the first nest member123 and the second nest member 124 in the respective axial directionsare the end points of the thermoplastic material channels 1231 and 1241.

The thermoplastic material channels 1231 and 1241 branch into pluralchannels between the start points to the end points. The branchedrespective plural thermoplastic material channels 1231 and 1241 extendtoward the ends of the first nest member 123 and the second nest member124 in the respective axial directions. The respective thermoplasticmaterial channels 1231 and 1241 are formed in a horn shape in which thewidth is gradually widened toward the end in the axial direction in thevicinity of one ends of the first nest member 123 and the second nestmember 124 in the respective axial directions. Further, in thehorn-shaped part, the bottom surface gradually approaches the innerperipheral surface (i.e., the thickness of the parts around the one endsof the first nest member 123 and the second nest member 124 in the axialdirection is thinned toward the ends in the axial direction).

Then the branched respective thermoplastic material channels 1231 and1241 are all joined and integrated in the position closest to the oneends in the respective axial direction in the first nest member 123 andthe second nest member 124 (position closest to the end points). Thatis, the outer peripheral surface sides at one ends of the first nestmember 123 and the second nest member 124 in the axial direction becomethe thermoplastic material channels 1231 and 1241 over the entire lengthin the circumferential direction.

When the first nest member 123 and the second nest member 124 areconnected, the thermoplastic material channels 1231 and 1241 formed inthe first nest member 123 and the second nest member 124 are joined inthe position closest to the one end in the axial direction. Accordingly,the tubular body formed by the connection between the first nest member123 and the second nest member 124 has a structure where thethermoplastic material channels 1231 and 1241 continuously surround overthe entire outer peripheral surface at one end of the through hole.Further, as described above, since the bottom surfaces of thethermoplastic material channels 1231 and 1241 are close to the innerperipheral surface in the vicinity of the one end in the axialdirection, (the end points of) the thermoplastic material channels 1231and 1241 are formed in the vicinity of the position closest to theoutside of the through hole of the tubular body formed by the connectionbetween the first nest member 123 and the second nest member 124.

More particularly, as the thermoplastic material channels 1231 and 1241,e.g. the following structure is applicable. The thermoplastic materialchannels 1231 and 1241 respectively have a predetermined position in theaxial direction and approximately in the middle of the circumferentialdirection as a start point. Then the channels extend from the startpoint toward the both sides in the circumferential direction,thereafter, turn and extend toward one end side in the axial direction.Then in a position front of the one end in the axial direction, thechannels respectively branch into two channels (total four channels).The branched respective thermoplastic material channels 1231 and 1241further extend toward the one end in the axial direction. Then thebranched respective thermoplastic material channels 1231 and 1241 areformed in a horn shape in which the width is gradually widened towardthe one end in a part where the outer peripheral surface is thin-noseshaped. Further, in this part, the bottom surfaces of the thermoplasticmaterial channels 1231 and 1241 gradually approach the inner peripheralsurface (i.e., the thickness of the first nest member 123 and the secondnest member 124 is gradually reduced) toward the one end in the axialdirection. Then, the respective thermoplastic material channels formedin a horn shape are all joined and integrated in the position closest tothe one end in the axial direction.

Note that the structure of the thermoplastic material channels 1231 and1241 is not limited to the above-described structure. That is, anystructure is applicable as long as in the respective first nest member123 and the second nest member 124, the thermoplastic material channels1231 and 1241 have the intermediate position of the outer peripheralsurface in the axial direction as the start point, and arrive at one endin the axial direction, and further, the channels are formed over theentire length (entire periphery) at one end in the axial direction.

The first case body member 121 has a structure in which the first nestmember 123 is fitted. The second case body member 122 has a structure inwhich the second nest member 124 is fitted. The first case body member121 in which the first nest member 123 is fitted and the second casebody member 122 in which the second nest member 124 is fitted can beseparably connected. Note that when the first case body member and thesecond case body member, in which the first nest member 123 and thesecond nest member 124 are respectively fitted, are connected, the firstnest member 123 and the second nest member 124 are also connected toform the tubular body.

Then the both ends of the through hole of the tubular body formed by theconnection between the first nest member 123 and the second nest member124 appear in the outer peripheral surface of the connected structure ofthe first case body member 121 and the second case body member 122. Thatis, the nozzle 12 in a state where the first case body member 121 andthe second case body member 122 are connected, as a whole has astructure to form a through hole which can accommodate the electric wire91 included in the predetermined part of the wire harness 9 according tothe embodiments of the present invention.

Referring to FIGS. 4 and 5, a fitting concave member 1211 in which thefirst nest member 123 is fitted is formed in the first case body member121. Similarly, a fitting concave member 1221 in which the second nestmember 124 is fitted is formed in the second case body member 122. Theinner peripheral surface of the fitting concave member 1211 formed inthe first case body member 121 is formed in a shape and size with whichthe outer peripheral surface of the first nest member 123 (hereinbelow,the surface as the outer peripheral surface of the tubular body formedby the connection between the first nest member 123 and the second nestmember 124) is approximately in close contact (except the thermoplasticmaterial channel 1231) when the first nest member 123 is fitted.

Accordingly, the fitting concave member 1211 formed in the first casebody member 121 is formed to have approximately the same shape and sizeas those of the outer peripheral surface of the first nest member 123.Similarly, the inner peripheral surface of the fitting concave member1221 formed in the second case body member 122 is formed in a shape anda size with which the outer peripheral surface of the second nest member124 (hereinbelow, the surface as the outer peripheral surface of thetubular body formed by the connection between the first nest member 123and the second nest member 124) is approximately in close contact (notethat except the thermoplastic material channel) when the second nestmember 124 is fitted. More particularly, for example, the fittingconcave member 1211 formed in the first case body member 121 is formedto have approximately the same shape and size as those of the outerperipheral surface of the first nest member 123, and the fitting concavemember 1221 formed in the second case body member 122 is formed to haveapproximately the same shape and size as those of the outer peripheralsurface of the second nest member 124.

Accordingly, when the first nest member 123 is fitted in the first casebody member 121, the thermoplastic material channel 1231 formed in thefirst nest member 123 is capped with the inner peripheral surface of thefitting concave member 1211 formed in the first case body member 121.Similarly, when the second nest member 124 is fitted in the second casebody member 122, the thermoplastic material channel 1241 formed in thesecond nest member 124 is capped with the inner peripheral surface ofthe fitting concave member 1221 formed in the second case body member122.

In a state where the first nest member 123 is fitted in the fittingconcave member 1211 formed in the first case body member 121, onesurface of the outer periphery of the first case body member 121approximately corresponds with an end surface at one end of the firstnest member 123 in the axial direction (end surface on the side of theend point of the thermoplastic material channel 1231). Similarly, in astate where the second nest member 124 is fitted in the fitting concavemember 1221 formed in the second case body member 122, one surface ofthe outer periphery of the second case body member 122 approximatelycorresponds with an end surface at one end of the second nest member 124in the axial direction. Accordingly, end surfaces of the first nestmember 123 and the second nest member 124 at their one ends in the axialdirection are exposed from the one surfaces of the respective outerperipheries of the first case body member and the second case bodymember.

Then, the outer peripheral surface (the bottom surface of thethermoplastic material channel 1231) in the position closest to the oneend of the first nest member 123 in the axial direction and the innerperipheral surface of the fitting concave member 1211 formed in thefirst case body member 121 are opposite to each other with apredetermined distance therebetween. That is, in one surface of theouter periphery of the first case body member 121, a predetermined gapis formed between the outer peripheral surface of the first nest member123 and the inner peripheral surface of the fitting concave member 1211formed in the first case body member 121. Similarly, in one surface ofthe outer periphery of the second case body member 122, a predeterminedgap is formed between the outer peripheral surface of the second nestmember 124 and the inner peripheral surface of the fitting concavemember 1221 formed in the second case body member 122. These gaps becomethe discharge orifices 1213 and 1223 (discharge orifices to dischargeplasticized thermoplastic material) of the nozzle 12.

The first nest member 123, fitted in the fitting concave member 1211formed in the first case body member 121, is fixed to the first casebody member 121. Similarly, the second nest member 124, fitted in thefitting concave member 1221 formed in the second case body member 122,is fixed to the second case body member 122. The first nest member 123and the second nest member 124 may be respectively attachable/removableto/from the first case body member 121 and the second case body member122. However, the first nest member 123 and the second nest member 124are fixed at least while the wire harness 9 according to the embodimentsof the present invention is manufactured. For example, a structure wherethe first nest member 123 and the second nest member 124 are removablyfixed with screws or the like is applicable (not shown).

When the first case body member 121 in which the first nest member 123is fitted and the second case body member 122 in which the second nestmember 124 is fitted are connected, one end of the through hole of thetubular body formed by the connection between the first nest member 123and the second nest member 124 appears in one surface of the outerperiphery of the connected structure of the first case body member 121and the second case body member 122. Then the discharge orifices 1213and 1223 are formed to surround the periphery of the one end of thethrough hole. For example, in a structure where the through hole of theconnected structure of the first nest member 123 and the second nestmember 124 is formed to have an approximate circular cross-sectionalshape, the through hole of the connected structure of the first nestmember 123 and the second nest member 124, the end surfaces at one endsof the first nest member 123 and the second nest member 124 in the axialdirection, the discharge orifices 1213 and 1223 to dischargethermoplastic material, and the inner peripheral surfaces of the fittingconcave members 1211 and 1221 of the first case body member 121 and thesecond case body member 122 are approximately coaxially arrayed.

Thermoplastic material channels 1212 and 1222 are formed in therespective first case body member 121 and the second case body member122. The thermoplastic material channels 1212 and 1222 are channels tofeed plasticized thermoplastic material to the start points of thethermoplastic material channels formed in the respective first nestmember 123 fitted in the first case body member 121 and the second nestmember 124 fitted in the second case body member 122. Therefore, forexample, the thermoplastic material channel 1212 formed in the firstcase body member 121 has a through hole shaped structure from the outerperiphery of the first case body member 121 to a predetermined position(the start point of the thermoplastic material channel 1231 formed inthe fitted first nest member 123) of the inner peripheral surface of thefitting concave member 1211. Similarly, the thermoplastic materialchannel 1222 formed in the second case body member 122 has a throughhole shaped structure from the outer periphery of the second case bodymember 122 to a predetermined position (the start point of thethermoplastic material channel 1241 formed in the fitted second nestmember 124) of the inner peripheral surface of the fitting concavemember 1221.

In this structure, when plasticized thermoplastic material is fed to therespective thermoplastic material channels 1212 and 1222 of the firstcase body member 121 and the second case body member 122, thethermoplastic material is discharged from the discharge orifices 1213and 1223 through the thermoplastic material channels 1212 and 1222formed in the respective first case body member 121 and the second casebody member 122 and the thermoplastic material channels 1231 and 1241formed in the respective first nest member 123 and the second nestmember 124.

Accordingly, inside the first case body member 121 in which the firstnest member 123 is fitted and the second case body member in which thesecond nest member 124 is fitted, the flow of the thermoplastic materialis as follows.

When the plasticized thermoplastic material is fed to the thermoplasticmaterial channels 1212 and 1222 in the first case body member 121 andthe second case body member 122, the plasticized thermoplastic materialflows through these thermoplastic material channels 1212 and 1222, andarrives at the start points of the thermoplastic material channels 1231and 1241 formed in the respective first nest member 123 and the secondnest member 124. Further, the thermoplastic material flows through thethermoplastic material channels 1231 and 1241 toward the end points (thedischarge orifices 1213 and 1223).

When the thermoplastic material flows through the thermoplastic materialchannels 1231 and 1241 from the start points toward the end points, thethermoplastic material also branches and flows in accordance with thebranch form of the thermoplastic material channels 1231 and 1241. Thebranched thermoplastic material flows are joined and integrated in aposition closest to one ends of the connected structure of the firstnest member 123 and the second nest member 124 in the axial direction.Then the thermoplastic material, in the integrated state, is dischargedfrom the discharge orifices 1213 and 1223. Since the discharge orifices1213 and 1223 continuously surround the periphery of the through hole ofthe tubular body formed by the connection between the first nest member123 and the second nest member 124, the discharged thermoplasticmaterial is formed in a continuous approximate tubular shape having across-sectional shape and size corresponding to the shape and size ofthe discharge orifices 1213 and 1223.

Note that in the first case body member 121 and the second case bodymember 122, other elements than the fitting concave members 1211 and1221 are not particularly limited as long as the flow of air in thevicinity of the discharge orifices 1213 and 1223 is not delayed (the airis easily sent to the thermoplastic material discharged from thedischarge orifices 1213 and 1223). For example, as respectively shown inFIGS. 5 and 6, the first case body member 121 and the second case bodymember 122 may have quadratic prism structures which form a through holein the axial direction when connected, or may have any other basaltiformshapes than quadratic prism shape having a polygonal cross-sectionalshape, or a columnar shape.

Note that the first case body member in which the first nest member 123is fitted and the second case body member in which the second nestmember 124 is fitted are connected so as to connect the first nestmember 123 with the second nest member 124 to form a tubular body.Accordingly, it may be arranged such that the first case body member 121and the second case body member 122 are aligned and connected so as toconnect the first nest member 123 with the second nest member 124 toform a tubular body. For example, it may be arranged such that in astate where the first case body member 121 and the second case bodymember 122 are connected, a projection is formed on one of mutuallyconnected or opposite surfaces, and a concave member is formed in theother surface. In this structure, it is possible to align and connectthe first case body member 121 with the second case body member 122 byengagement of the projection formed on one of the first case body member121 and the second case body member 122 with the concave member formedin the other member.

The air blowing unit 13 cools down the thermoplastic material (formedcovering member 92), discharged from the discharge orifices 1213 and1223 of the first case body member 121 and the second case body member122 (i.e. the nozzle 12), in a position closest to the dischargeorifices 1213 and 1223. Accordingly, the air blowing unit 13 has astructure to send air to the position closest to the discharge orifices1213 and 1223 of the first case body member 121 and the second case bodymember 122.

Note that the structure of the air blowing unit 13 is not limited, butvarious conventionally known air blowing units are applicable. Forexample, a structure having an air compressor or an air tank and a blasttube or a blower tube, to send air in the air compressor or the air tanktoward the discharge orifices 1213 and 1223 of the first case bodymember 121 and the second case body member 122 through the blast tube orthe blower tube (the end on the side to discharge the air in the blasttube or the blower tube is provided in a position closest to the firstcase body member 121 and the second case body member 122) is applicableas the air blowing unit 13. In addition, a structure where a blower fan(various conventionally known fans are applicable as the blower fan) isprovided in the vicinity of the discharge orifices 1213 and 1223 isapplicable.

Note that as the air blowing unit 13, any structure is applicable aslong as it blows area at normal temperatures, and it is not necessary toprovide the structure with an air temperature control mechanism.Further, it is not necessary for the air blowing unit 13 to have astructure to cool down the first case body member 121 and the secondcase body member 122. That is, any structure is applicable as long as itcools down the thermoplastic material discharged torn the dischargeorifices 1213 and 1223 of the first case body member 121 and the secondcase body member 122 to a temperature at which plastic deformation bythermal plasticity does not occur (or a temperature at which the plasticdeformation by thermal plasticity is suppressed). Accordingly, thecooling capability (air blowing capability) of the air blowing unit 13is sufficient as long as it cools down the thermoplastic material to atemperature at which plastic deformation by thermal plasticity does notoccur. A cooling capability to cool the first case body member 121 andthe second case body member 122 is not required.

Next, regarding a wire harness manufacturing apparatus 2 according to asecond embodiment of the present invention, mainly a difference from thewire harness manufacturing apparatus 1 according to the above-describedfirst embodiment will be described.

FIG. 8 is a perspective diagram schematically showing the structures ofprincipal elements of the wire harness manufacturing apparatus 2according to the second embodiment of the present invention. As shown inFIG. 8, the wire harness manufacturing apparatus 2 according to thesecond embodiment of the present invention has the material plasticizingunit 11, a nozzle 22 and an air blowing unit 13. Among these units, thematerial plasticizing unit 11 and the air blowing unit 13 have the samestructures as those in the wire harness manufacturing apparatus 1according to the first embodiment. That is, the structure of the nozzle22 in the wire harness manufacturing apparatus 2 according to the secondembodiment is different from the nozzle 12 in the wire harnessmanufacturing apparatus 1 according to the first embodiment.

The nozzle 22 is a tool to mold the covering member 92 by dischargingthe thermoplastic material plasticized with the material plasticizingunit 11 so as to cover the periphery of the electric wire 91 in the wireharness 9. FIG. 9 is an exploded external perspective diagram showingthe structures of respective elements of the nozzle 22. FIG. 10 is across-sectional diagram along a line C-C in FIG. 9. FIG. 11 is anexternal perspective diagram showing a state where the nozzle 22 isbuilt. FIG. 12A is a plane diagram showing a first tabular member 223(second tabular member 224). FIG. 13 is a cross-sectional diagram alonga line D-D in FIG. 12 in a state where a first lid member 221 (secondlid member 222) is fixed.

As shown in FIGS. 9 to 10, the nozzle 22 has the first lid member 221,the second lid member 222, the first tabular member 223 and the secondtabular member 224. The first lid member 221 can be fixed to the firsttabular member 223, and the second lid member 222 can be fixed to thesecond tabular member 224. The first tabular member 223 and the secondtabular member 224 are separably connected in a planar direction (XYplanar direction in FIG. 11, i.e. planar direction orthogonal to athickness direction of the tabular member). Since the first lid member221 and the second lid member 222 are fixed to the respective firsttabular member 223 and the second tabular member 224, thermoplasticmaterial discharge orifices (hereinbelow, simply referred to as“discharge orifices”) 2232 and 2242 are formed. When the first tabularmember 223 and the second tabular member 224 are connected, thedischarge orifices 2232 and 2242 are integrated. It is possible to moldthe approximate tubular-shaped covering member 92 by discharging theplasticized thermoplastic material from the discharge orifices 2232 and2242.

The first tabular member 223 and the second tabular member 224 can beseparably connected. When the first tabular member 223 and the secondtabular member 224 are connected, one tabular body (tabular structure inwhich a through hole is formed through a direction orthogonal to theplanar direction) is formed.

The first tabular member 223 and the second tabular member 224 can beconnected with the electric wire 91, included in a predetermined part ofthe wire harness 9 according to the embodiments of the presentinvention, between the two members. That is, the tabular body formed bythe connection between the first tabular member 223 and the secondtabular member 224 can accommodate the electric wire 91, included in thepredetermined part of the wire harness 9 according to the embodiments ofthe present invention, in the through hole (the electric wire 91 isinserted through the through hole). Then, in a state where the electricwire 91, included in the predetermined part of the wire harness 9according to the embodiments of the present invention, is accommodatedin the through hole of the tabular body formed by the connection betweenthe first tabular member 223 and the second tabular member 224, thetabular body formed by the connection between the first tabular member223 and the second tabular member 224 and the electric wire 91 includedin the predetermined part of the wire harness 9 according to theembodiments of the present invention can relatively move along the axialdirection of the electric wire 91.

Accordingly, the through hole of the tabular body formed by theconnection between the first tabular member 223 and the second tabularmember 224 has a shape and a size to accommodate the electric wire 91included in the predetermined part of the wire harness 9 according tothe embodiments of the present invention. More precisely, as describedlater, since the through hole of the tabular body is covered withuniform parts 2211 b and 2221 b of projections 2211 and 2221 in thefirst lid member 221 and the second lid member 222, the through holeformed with the uniform parts 2211 b and 2221 b may have any shape andsize as long as the through hole accommodates the electric wire 91included in the predetermined part of the wire harness 9 according tothe embodiments of the present invention (see FIG. 13). Further, thecross-sectional shape and size of the tabular body formed by theconnection between the first tabular member 223 and the second tabularmember 224 define the cross-sectional shape and size of the coveringmember 92. Further, when plural electric wires 91 are included in thepredetermined part of the wire harness 9 according to the embodiments ofthe present invention, the cross-sectional shape and size of the tabularbody define the cross-sectional shape of the bundled electric wires 9.Accordingly, when the cross-sectional shape of the covering member 92 isformed in an approximate circular shape and plural electric wires 91 arebundled to have an approximate circular cross-sectional shape, anapproximate circular shape is applied as the cross-sectional shape ofthe through hole of the tabular body formed by the connection betweenthe first tabular member 223 and the second tabular member 224.

The first tabular member 223 and the second tabular member 224 haverelatively thin flat plate members 223 a and 224 a and relatively thickhose engagement members 223 b and 224 b. Thermoplastic material channels2231 and 2241 to be described in detail later are formed in surfaces ofthe first tabular member 223 and the second tabular member 224 on theside orthogonal to the thickness direction of the flat plate members 223a and 224 a. Concave members 223 b 1 and 224 b 1 engaged with hoses areformed in the hose engagement members 223 b and 224 b of the firsttabular member 223 and the second tabular member 224. Thermoplasticmaterial channels 2212 and 2222, communicating with the thermoplasticmaterial channels 2231 and 2241, formed in the flat plate members 223 aand 224 a of the first tabular member 223 and the second tabular member224, are formed in bottom surfaces of the respective concave members 223b 1 and 224 b 1.

The thermoplastic material channels 2231 and 2241 are formed in therespective first tabular member 223 and the second tabular member 224.Note that the thermoplastic material channel 2231 of the first tabularmember 223 and the thermoplastic material channel 2241 of the secondtabular member 224 are bilaterally symmetrical with surfaces of thefirst tabular member 223 and the second tabular member 224 in contactwith each other are symmetrical surfaces. As shown in FIG. 11, thethermoplastic material channels 2231 and 2241 are grooves formed in thesurface of one of the respective flat plate members 223 a and 224 a ofthe first tabular member 223 and the second tabular member 224 (surfacein close contact with the first lid member or the second lid member). Asshown in FIGS. 9 and 11, in the surface of one of the respective flatplate members 223 a and 224 a of the first tabular member 223 and thesecond tabular member 224, the thermoplastic material channels 2231 and2241 have predetermined positions on the side of the hose engagementmembers 223 b and 224 b as start points, and positions facing thethrough hole as end points (arrive at positions facing the throughhole).

The thermoplastic material channels 2231 and 2241 branch into pluralchannels between the start points and the end points. The branchedrespective thermoplastic material channels 2231 and 2241 extend toward adirection to approach the through hole. Then in the vicinity of thethrough hole, the respective thermoplastic material channels 2231 and2241 are formed in a horn shape in which the width is gradually widenedtoward the through hole in the axial direction. Further, in the hornshaped part, one surface gradually approaches the opposite surface(i.e., in a part in the vicinity of the through hole in the flat platemembers 223 a and 224 a of the first tabular member 223 and the secondtabular member 224, the thickness is reduced toward the through hole).

When the branched respective thermoplastic material channels 2231 and2241 arrive at the through hole, all the channels are joined andintegrated. That is, the thermoplastic material flows over the entirelength in the circumferential direction outside the through hole formedby the connection between the first tabular member 223 and the secondtabular member 224.

When the first tabular member 223 and the second tabular member 224 areconnected, the thermoplastic material channels 2231 and 2241 formed inthe respective first tabular member 223 and the second tabular member224 are joined around the through hole. That is, the discharge orifices2232 and 2242 continuously surround the entire outer peripheral surfaceof the through hole at one end.

More particularly, as the thermoplastic material channels 2231 and 2241,the following structure, for example, is applicable. The thermoplasticmaterial channels 2231 and 2241 have predetermined positions on the sideof the hose engagement members 223 b and 224 b as start points. Then,the thermoplastic material channels 2231 and 2241 extend from the startpoints by a predetermined length in the planar direction of the flatplate members 223 a and 224 a, and branch into two channels. Further,the channels extend by a predetermined length in the planar direction ofthe flat plate members 223 a and 224 a, and respectively branch into twochannels (branch into total four channels). The branched respectivethermoplastic material channels 2231 and 2241 extend while turning in adirection to approach the through hole. Then the branched respectivethermoplastic material channels 2231 and 2241 are formed in a horn shapein which the width is gradually widened toward the through hole in thevicinity of the periphery of the through hole. Further, in this part,one surface gradually approaches the opposite surface in a direction toapproach the through hole (i.e., in the flat plate members 223 a and 224a of the first tabular member 223 and the second tabular member 224, thethickness is gradually reduced toward the through hole). When thechannels arrive at the through hole, all the channels are joined andintegrated.

Note that the structure of the thermoplastic material channels 2231 and2241 is not limited to the above-described structure. That is, anystructure is applicable as long as the thermoplastic material channels2231 and 2241 are formed to extend in the planar direction of the flatplate members 223 a and 224 a and to be joined around the through holein the respective first tabular member 223 and the second tabular member224.

The first lid member 221 is fixed to the first tabular member 223. Thesecond lid member 222 is fixed to the second tabular member 224. Moreparticularly, the first lid member 221 is fixed such that a plane partof the first lid member 221 is in close contact with one surface of theflat plate member 223 a of the first tabular member 223. Similarly, thesecond lid member 222 is fixed such that a plane part of the second lidmember 222 is in close contact with one surface of the flat plate member224 a of the second tabular member 224. Accordingly, when the first lidmember 221 is fixed to the first tabular member 223, the thermoplasticmaterial channel 2231 formed in the first tabular member 223 is cappedwith the first lid member 221. Similarly, when the second lid member 222is fixed to the second tabular member 224, the thermoplastic materialchannel 2241 formed in the second tabular member 224 is capped with thesecond lid member 222.

Further, the first lid member 221 and the second lid member 222 have theprojections 2211 and 2221 projected in a cylindrical shape from theplanar parts. As shown in FIG. 11, the projections 2211 and 2221 havetaper parts 2211 a and 2221 a in which the thickness in the radialdirection is gradually reduced and the uniform parts 2211 b and 2221 bin which the thickness in an extending direction from the ends of thetaper parts are constant. In a state where the first lid member 221 isfixed to the first tabular member 223, the ends of the projections 2211and 2221 of the first lid member 221 approximately correspond to thesurface on the discharge orifice 2232 of the first tabular member 223(surface on the opposite side to the surface where the thermoplasticmaterial channel 2231 is formed). Similarly, in a state where the secondlid member 222 is fixed to the second tabular member 224, the ends ofthe projections 2211 and 2221 of the second lid member 222 approximatelycorrespond to the surface on the discharge orifice 2242 of the secondtabular member 224 (surface on the opposite side to the surface wherethe thermoplastic material channel 2241 is formed). Accordingly, theends of the projections 2211 and 2221 of the first lid member 221 andthe second lid member 222 are exposed from the surfaces on the side ofthe respective discharge orifices 2232 and 2242 of the first tabularmember 223 and the second tabular member 224.

Then, as shown in FIG. 13, in the thermoplastic material channels 2231and 2241, in the vicinity of the through hole, the horn shaped parts inwhich the width is gradually widened toward the through hole are cappedwith the taper parts 2211 a and 2221 a of the projections 2211 and 2221in the first lid member 221 and the second lid member 222. On the otherhand, the outer peripheral surfaces of the uniform parts 2211 b and 2221b of the projections 2211 and 2221 are opposite to the inner peripheralsurface of a through hole formed by the connection between the firsttabular member 223 and the second tabular member 224 with apredetermined distance therebetween. That is, a predetermined gap isformed between the uniform parts 2211 b and 2221 b of the projections2211 and 2221 and the through hole. The end of the gap becomes thedischarge orifices 2232 and 2242 of the nozzle 22 (the dischargeorifices 2232 and 2242 to discharge the plasticized thermoplasticmaterial).

Note that the first lid member 221 and the second lid member 222 may berespectively separably fixed to the first tabular member 223 and thesecond tabular member 224. However, at least while the wire harness 9according to the embodiments of the present invention is manufactured,the first lid member 221 and the second lid member 222 are maintained inthe fixed state. For example, as shown in FIG. 11, a structure where thefirst lid member 221 and the second lid member 222 are separably fixedwith screws or the like is applicable.

The thermoplastic material channels 2212 and 2222 are formed in therespective hose engagement member 223 b of the first lid member 221 andthe hose engagement member 224 b of the second lid member 222 (see FIG.10). The thermoplastic material channels 2212 and 2222 are channels tofeed the plasticized thermoplastic material to the start points of thethermoplastic material channels 2231 and 2241 formed in the respectiveflat plate member 223 a of the first tabular member 223 capped with thefirst lid member 221 and flat plate member 224 a of the second tabularmember 224 capped with the second lid member 222. Accordingly, forexample, the thermoplastic material channel 2212 formed in the hoseengagement member 223 b of the first tabular member 223 has athrough-hole shaped structure formed from the bottom surface of theconcave member 223 b 1 of the hose engagement member 223 b of the firsttabular member 223 to the flat plate member 223 a side (the start pointof the thermoplastic material channel 2231 formed in the flat platemember 223 a of the first tabular member 223). Similarly, thethermoplastic material channel 2222 formed in the hose engagement member224 b of the second tabular member 224 has a through-hole-shapedstructure formed from the bottom surface of the concave member 224 b 1of the hose engagement member 224 b of the second tabular member 224 tothe flat plate member 224 a side (the start point of the thermoplasticmaterial channel 2241 formed in the flat plate member 224 a of thesecond tabular member 224).

According to the above structure, when the plasticized thermoplasticmaterial is fed to the respective thermoplastic material channels 2212and 2222 of the hose engagement member 223 b of the first tabular member223 and the hose engagement member 224 b of the second tabular member224, the thermoplastic material is discharged from the dischargeorifices 2232 and 2242 through the thermoplastic material channels 2231and 2241 formed in the flat plate member 223 a of the first tabularmember 223 and the flat plate member 224 a of the second tabular member224.

Accordingly, inside the first tabular member 223 to which the first lidmember 221 is fixed and the second tabular member 224 to which thesecond lid member 222 is fixed, the flow of the thermoplastic materialis as follows.

When the plasticized thermoplastic material is fed to the thermoplasticmaterial channels 2212 and 2222 formed in the respective hose engagementmember 223 b of the first tabular member 223 and the hose engagementmember 224 b of the second tabular member 224, the plasticizedthermoplastic material flows through these thermoplastic materialchannels 2212 and 2222, and arrives at the start points of thethermoplastic material channels 2231 and 2241 formed in the respectiveflat plate member 223 a of the first tabular member 223 and the flatplate member 224 a of the second tabular member 224. Further, thethermoplastic material flows through the thermoplastic material channels2231 and 2241 toward the end points.

Since several branches exist between the start points and the end pointsin the thermoplastic material channels 2231 and 2241, the thermoplasticmaterial branches and flows in accordance with the branch form of thethermoplastic material channels 2231 and 2241. Since the thermoplasticmaterial channels 2231 and 2241 are formed so as to extend in the planardirection, the thermoplastic material flows in the planar direction.When the branch flows of the thermoplastic material pass through thehorn part in which the width is gradually widened toward the throughhole in the vicinity of the through hole, the branches are joined andintegrated at the gap between the uniform parts 2211 b and 2221 b of theprojections 2211 and 2221 of the first lid member 221 and the second lidmember 222 and the through hole of the tabular body formed by theconnection between the first tabular member 223 and the second tabularmember 224. Then the thermoplastic material, in the integrated state, isdischarged to the outside from the discharge orifices 2232 and 2242.Since the discharge orifices 2232 and 2242 continuously surround theperiphery of one end of the through hole of the tabular body formed bythe connection between the first tabular member 223 and the secondtabular member 224, the discharged thermoplastic material is formed in acontinuous approximate tubular shape having a cross-sectional shape anda size corresponding to the shape and the size of the discharge orifices2232 and 2242.

Note that the first lid member 221 and the second lid member 222 may beformed with heater panels to increase the fluidity of the thermoplasticmaterial flowing through the thermoplastic material channels 2231 and2241.

As a modification of the above-described wire harness manufacturingapparatus 2 according to the second embodiment, the following examplecan be given.

As shown in FIG. 11, the thermoplastic material channels 2231 and 2241have predetermined positions on the side of the hose engagement members223 b and 224 b as start points, and extend from the start points in theplanar direction of the flat plate members 223 a and 224 a by apredetermined length, and branch into two channels. Further, thechannels extend in the planar direction of the flat plate members 223 aand 224 a by a predetermined length, and respectively branch into twobranches, i.e., total four branches. Since the thermoplastic materialchannels 2231 and 2241 formed in this manner are formed so as to extendin the planar direction different from the direction in the firstembodiment, the length from the start points to the end points of therespective channels are different.

Accordingly, assuming that the respective channels have the samecross-sectional area, the resistance (line resistances) to thethermoplastic material flowing through the respective branched channelsis high when the channel is long. Accordingly, in consideration ofpressure loss due to such resistance, it is preferable that, regardingthe thermoplastic material channels 2231 and 2241, the cross-sectionalarea of a channel having a long length from the start point to the endpoint is increased. For example, in the structure shown in FIG. 11, thechannel extending around the farthest part from the through hole in theplanar direction (the leftmost channel in FIG. 11) is the longest.Accordingly, the cross-sectional area of this channel is the greatest.The length of a channel extending around a part near the through hole isshort (in FIG. 11, the length is shorter toward the right side).Accordingly, the channel cross-sectional area is reduced in accordancewith reduction of the channel length.

Next, a wire harness manufacturing method according to the embodimentsof the present invention will be described. Hereinbelow, a manufacturingmethod using the wire harness manufacturing apparatus according to thefirst embodiment will be described.

First, respectively predetermined connectors and the like are attachedto the ends of the respective electric wires 91 included in the wireharness 9 according to the embodiments of the present invention. Thisprocess can be performed in a stage prior to the binding of the electricwires 91 in a predetermined form or in a stage prior to the molding ofthe covering member 92. Accordingly, the process can be performed usinga device to automatically attach the connectors and the like to the endsof the electric wires 91 (hereinbelow, simply referred to as an“automatic device”).

In a stage after the binding of the electric wires 91 included in thewire harness 9 according to the embodiments of the present invention ina predetermined form or a stage after the molding of the covering member92, it may be impossible to set predetermined electric wires in theautomatic device due to interference by other electric wires 91 and thecovering member 92. In such case, it is impossible to attach theconnectors and the like to the electric wires 91 using the automaticdevice and it is necessary to manually attach the connectors and thelike. On the other hand, in the wire harness manufacturing methodaccording to the embodiments of the present invention, the connectorsand the like can be attached in a stage prior to the binding of theelectric wires 91 in a predetermined form or a stage prior to themolding of the covering member 92 (that is, the connectors and the likecan be attached to the respective electric wires 91 in an unboundstate). Accordingly, the use of the automatic device is not prevented.

Next, the electric wires 91 included in the wire harness 9 according tothe embodiments of the present invention are bundled in a predeterminedform (a predetermined trunk line and predetermined branch lines areformed). This operation is performed using e.g. a drawing board or thelike on which the form of the electric wires 91 in the wire harness 9 ofthe present invention. The content of the operation is the same as aconventional operation. Further, as the drawing board, a conventionallyknown board is applicable. Accordingly, the explanation of the operationwill be omitted.

Next, the covering member 92 is formed in a predetermined part of thebundled electric wires 91. More particularly, the formation of thecovering member 92 is performed as follows. FIGS. 14 to 17 schematicallyshow the processes of molding the covering member 92.

First, as shown in FIG. 14, a predetermined part of the electric wires91 (one end of a part where the covering member 92 is formed in theaxial direction) is held between the first case body member 121 in whichthe first nest member 123 is fitted and the second case body member 122in which the second nest member 124 is fitted (i.e., with the nozzle12). Then, the first case body member 121 and the second case bodymember 122 are connected. In this state, the one end of thepredetermined part of the electric wires 91 in the axial direction isaccommodated in the through hole of the tubular body formed by theconnection between the first nest member 123 and the second nest member124.

The first nest member 123 and the second nest member 124 have structuresobtained by dividing a tubular body into halves along the axialdirection. Accordingly, by bringing the first nest member 123 and thesecond nest member 124 from side positions of the electric wires 91 andconnecting the first nest member 123 and the second nest member 124 withthe electric wires 91 therebetween, the predetermined part of theelectric wires 91 can be accommodated in the through hole of the tubularbody formed by the connection between the first nest member 123 and thesecond nest member 124. Accordingly, it is not necessary to insert theelectric wires from one end of the through hole of the tubular bodyformed by the connection between the first nest member 123 and thesecond nest member 124. Even when the connectors and the like areattached to the ends of the electric wires 91, the connectors and thelike do not disturb this operation. In this manner, in the wire harnessmanufacturing method according to the embodiments of the presentinvention, the order of attachment of the connectors and the like to theends of the electric wires 91 and the molding the covering member 92 ina predetermined part of the electric wire 91 is not limited.Accordingly, when the connectors and the like have been attached to theends of the electric wire 91, the covering member 92 can be molded inthe predetermined part of the electric wires 91.

On the other hand, in the method of inserting the predetermined part ofthe electric wires 91 into the through hole of the connected structureof the first nest member 123 and the second nest member 124, when theconnectors attached to the ends of the electric wires 91 are greaterthan the inner diameter of the through hole, the predetermined part ofthe electric wire 91 cannot be inserted into the through hole.

Then, the thermoplastic material is heated with the materialplasticizing unit 11 to a predetermined temperature and is plasticized,and the plasticized thermoplastic material is sent through the hose 14to the thermoplastic material channels 1212 and 1222 formed in the firstcase body member 121 and the second case body member 122 of the nozzle12. The thermoplastic material sent to the thermoplastic materialchannels 1212 and 1222 formed in the first case body member 121 and thesecond case body member 122 flows through the thermoplastic materialchannels 1212 and 1222 and arrives at the thermoplastic materialchannels 1231 and 1241 formed in the first nest member 123 and thesecond nest member 124. Further, the thermoplastic material flowsthrough the thermoplastic material channels 1231 and 1241 formed in thefirst nest member 123 and the second nest member 124 toward thedischarge orifices 1213 and 1223.

When the plasticized thermoplastic material flows through thethermoplastic material channels 1231 and 1241 formed in the first nestmember 123 and the second nest member 124 toward the discharge orifices1213 and 1223, the thermoplastic material also branches and flows inaccordance with the branch form of the thermoplastic material channels1231 and 1241. The branched thermoplastic material flows are joined in aposition closest to one end of the connected structure of the first nestmember 123 and the second nest member 124 in the axial direction,combined and integrated.

Then the thermoplastic material, in the integrated state, is dischargedfrom the discharge orifices 1213 and 1223 of the first case body member121 and the second case body member 122 of the nozzle 12 to the outsideof these members (i.e., the outside the nozzle 12).

The discharge orifices 1213 and 1223 formed in the nozzle 12 are formedin the closest vicinity of the outside of the through hole of thetubular body formed by the connection between the first nest member 123and the second nest member 124, so as to continuously surround thethrough hole. Accordingly, the thermoplastic material discharged fromthe discharge orifices 1213 and 1223 of the first case body member 121and the second case body member 122 of the nozzle 12 covers theperiphery of the electric wires 91, and is formed in an approximatetubular shape, and becomes the covering member 92. As the thermoplasticmaterial channels 1231 and 1241 formed in the first nest member 123 andthe second nest member 124 are joined in the closest vicinity of thedischarge orifices 1213 and 1223, the thermoplastic material flows arealso joined, combined and integrated. Accordingly, the covering member92 is integrally formed of the thermoplastic material without seam ordiscontinuity.

The temperature of the thermoplastic material, newly discharged from thedischarge orifices 1213 and 1223, (the covering member 92 immediatelyafter the molding) is at a plastic-deformable temperature by thermoplasticity, and the thermoplastic material is soft so that the plasticdeformation is possible by application of external force. Further, thetemperature of the thermoplastic material is lower than that immediatelyafter injection in general injection molding or that immediately afterpressing in general press molding, and is in a plastic-undeformablestate in comparison with these states. In this manner, as the dischargedand molded covering member 92 has low fluidity (it does not flow unlessit receives an external force, that is, it hardly flows by its ownweight or the like), it does not enter a gap between the electric wires91. Note that there is a possibility that the thermoplastic materialenters the gap between the electric wires 91 when this state ismaintained for many hours. However, since the temperature of thedischarged thermoplastic material is low, when the thermoplasticmaterial is exposed to ambient air (normal temperature air), thetemperature is lowered to a temperature at which the plastic deformationby thermo plasticity does not occur before the thermoplastic materialenters the gap between the electric wires 91. In this manner, thedischarged covering member 92 does not enter the gap between theelectric wires 91 and connect the electric wires.

Accordingly, in the wire harness manufacturing method according to theembodiments of the present invention, in comparison with the structurewhere a tape is wrapped around the electric wires, the structure wherethe covering member is formed by injection molding and the structurewhere the periphery of the electric wire is coated with plasticizedthermoplastic material, degradation of the flexibility of thepredetermined part of the electric wire (the part in which the coveringmember is molded) (especially bendability) can be prevented orsuppressed.

That is, in the structure where the tape is wrapped around the electricwires, since the electric wires are fastened with the tape, the electricwires are in close contact as if they thrust each other at predeterminedpressure. Accordingly, since the predetermined part is in a state as ifall the electric wires were integrally attached, the flexibility of thetape-wrapped part is lowered. Further, in the structure where thecovering member is formed by injection molding and the structure wherethe covering member is formed by coating the electric wires with theplasticized thermoplastic material, the injected thermoplastic materialor the applied thermoplastic material enters a gap between the electricwires and connects the electric wires. Further, the gap between theelectric wires is filled with the thermoplastic material. Accordingly,since the part enters a state as if all the electric wires wereintegrally connected, and no hollow exists between the electric wires,the flexibility of the part in which the covering member is formed islowered.

On the other hand, according to the wire harness manufacturing methodaccording to the embodiments of the present invention, it is possible tomanufacture a wire harness having a structure in which the moldedcovering member 92 does not firmly connect the electric wires 91.Further, it is possible to manufacture a wire harness having a structurein which the thermoplastic material does not enter a gap between theelectric wires. According to the wire harness manufacturing methodaccording to the embodiments of the present invention, it is possible tomanufacture a wire harness in which the flexibility of a part where thecovering member 92 is formed is not lowered.

A part of the inner peripheral surface of the covering member 92discharged from the discharge orifices 1213 and 1223 and formed in anapproximate tubular shape is in contact with a part or the entiresurface of the electric wires 91. The covering member 92 immediatelyafter the discharge from the discharge orifices 1213 and 1223 is in aplastic-deformable state by thermo plasticity, and its surface hasviscosity. Accordingly, in the inner peripheral surface of the coveringmember 92, a part in contact with the electric wires 91 is attached tothe electric wires 91.

As described above, when single or a small number of electric wires 91are included in the predetermined part of the wire harness 9 accordingto the embodiments of the present invention, as the inner peripheralsurface of the covering member 92 is in contact with the outerperipheral surfaces of all the electric wires 91, all the electric wires91 are attached to the inner peripheral surface of the covering member92. On the other hand, when a large number of electric wires 91 areincluded in the predetermined part, an electric wire surrounded withother electric wires 91 and not exposed the outside of the bundle of theelectric wires 91 is not in contact with the inner peripheral surface ofthe covering member 92. Especially, as described above, the coveringmember 92 discharged from the discharge orifices 1213 and 1223 has a lowfluidity, accordingly, it does not enter a gap between the electricwires 91 to arrive at and in contact with the surface of the unexposedelectric wire 91. Accordingly, the inner peripheral surface of thecovering member 92 is not attached to such electric wire 91.Accordingly, in this case, a structure where the inner peripheralsurface of the covering member 92 is attached to a part of the pluralelectric wires 91 is obtained.

As shown in FIG. 15, while the thermoplastic material is discharged fromthe discharge orifices 1213 and 1223, the predetermined part of theelectric wire 91 and the nozzle 12 (the connected structure of the firstcase body member 121 and the second case body member 122) are relativelymoved along their axial directions. Then the covering member 92 isformed within the range of the relative movement in the predeterminedpart of the electric wires 91.

Note that as long as the size of the predetermined part of the electricwires 91 is set such that it can be accommodated in the through hole ofthe tubular body formed by the connection between the first nest member123 and the second nest member 124, it is possible to mold the coveringmember 92 regardless of the outer diameter of the electric wire 91 (whenplural electric wires 91 are included, the outer diameter of the entirebundle of the electric wires 91). Accordingly, even when the diameter ofthe predetermined part of the electric wire 91 is changed in the middleof the axial direction, the molding of the covering member 92 can becontinued by continuing the relative movement between the nozzle 12 andthe electric wire 91 and the discharge of the thermoplastic material. Asa result, in the predetermined part of the electric wire 91, thecovering member 92 can be molded integrally over the parts havingdifferent outer diameters. That is, as long as the outer diameter of theelectric wire 91 has a size that the electric wire can be accommodatedin the through hole of the tubular body formed by the connection betweenthe first nest member 123 and the second nest member 124, even when theouter diameter is changed in the middle of the axial direction, themolding of the covering member 92 can be continued without change ofnozzle 12.

The thickness of the molded covering member 92 is determined incorrespondence with the amount of thermoplastic material discharged fromthe discharge orifices 1213 and 1223 of the nozzle 12 per unit time andthe speed of relative movement between the nozzle 12 and the electricwires 91. That is, when the amount of the thermoplastic materialdischarged from the discharge orifices 1213 and 1223 per unit time isincreased or the speed of relative movement between the nozzle 12 andthe electric wires 92 is reduced, the thickness of the molded coveringmember 92 is increased. In this manner, it is possible to control thethickness of the molded covering member 92 by controlling at least oneof the amount of the thermoplastic material discharged from thedischarge orifices 1213 and 1223 per unit time and the speed of relativemovement between the nozzle 12 and the predetermined part of theelectric wires 91.

Accordingly, when the amount of the thermoplastic material dischargedfrom the discharge orifices 1213 and 1223 per unit time and the speed ofrelative movement between the nozzle 12 and the predetermined part ofthe electric wires 91 are constant, the thickness of the molded coveringmember 92 is approximately uniform over the entire length in the axialdirection. That is, the covering member 92 as shown in FIG. 1 is formed.On the other hand, it is possible to mold the covering member 92 inwhich the thickness changes along the axial direction by changing one orboth of the amount of the thermoplastic material discharged from thedischarge orifices 1213 and 1223 per unit time and the speed of relativemovement between the nozzle 12 and the predetermined part of theelectric wires 91 in the middle. That is, the covering member 92 asshown in FIG. 2 is formed. In this manner, it is possible to integrallymold the covering member 92 in which the thickness changes along theaxial direction not by attaching another part but by discharging thethermoplastic material.

In this structure, even when the predetermined part of the electricwires 91 is to be especially protected, it is not necessary to attachanother part as a protector member. Further, it is possible to controlthe thickness of the covering member 92 by controlling one or both ofthe speed of relative movement between the nozzle 12 and thepredetermined part of the electric wires 91 and the amount of thethermoplastic material discharged from the discharge orifices 1213 and1223 of the nozzle 12 per unit time. Accordingly, it is possible toeasily control the shape and size of the covering member 92 and avoidincrement in the number of process steps. Accordingly, it is possible tosuppress the rise of manufacturing cost or reduce the manufacturingcost.

When the nozzle 12 and the predetermined part of the electric wires 91are relatively moved and the nozzle 12 is positioned at the other end ofthe predetermined part of the electric wires 91 (the other end of thepart where the covering member 92 is formed) (i.e., when the coveringmember 92 is formed in the predetermined part of the electric wires 91),the relative movement between the nozzle 12 and the predetermined partof the electric wires 91 is stopped, and the discharge of thethermoplastic material is stopped.

Thereafter, as shown in FIG. 16, the air blowing unit 13 sends air to atleast a part of the molded covering member 92 closest to the dischargeorifices 1213 and 1223 of the nozzle 12. When the air is sent to themolded covering member 92, the temperature of the molded covering member92 is lowered, and the covering member 92 is in a state where plasticdeformation by thermo plasticity does not occur. Further, thereafter, asshown in FIG. 17, when the nozzle 12 and the predetermined part of theelectric wires 91 are relatively moved, the molded covering member 92 iscut from the thermoplastic material remaining in the nozzle 12(thermoplastic material to be molded in the covering member 92) at thedischarge orifices 1213 and 1223 of the nozzle 12, and separated fromthe nozzle 12.

In the above structure, it is possible to cut the molded covering member92 without plastic deformation to pull it out. Accordingly, it ispossible to improve the appearance of the end of the covering member 92in the axial direction.

That is, the covering member 92 newly discharged from the dischargeorifices 1213 and 1223 of the nozzle 12 is at a plastic-deformabletemperature by thermo plasticity. Accordingly, in this state, when thenozzle 12 and the predetermined part of the electric wires 91 arerelatively moved, the discharged and molded covering member 92 is pulledout and plastic-deformed. The end of the covering member 92 is flaggy,and the appearance is bad. Note that in a position closest to thedischarge orifices 1213 and 1223 of the nozzle 12, since the moldedcovering member 92 is in a plastic-deformable state by thermoplasticity, it is difficult to cut the covering member. Further, when acutting tool is used to cut the covering member 92, there is aprobability of damaging the electric wires 91 with this cutting tool.

On the other hand, according to the wire harness manufacturing methodaccording to the embodiments of the present invention, it is possible tocut the molded covering member 92 to have a good appearance for thefollowing reason. When the air blowing unit 13 sends air to at least apart of the molded covering member 92 closest to the discharge orifices1213 and 1223 of the nozzle 12, this part of the covering member 92 isquickly cooled down. Accordingly, in this part of the covering member92, plastic deformation by thermo plasticity does not occur. On theother hand, since the thermoplastic material existing in the nozzle 12does not receive air sent from the air blowing unit 13, it is in aplastic-deformable state by thermo plasticity. As a result, thethermoplastic material (including the molded covering member 92) has aborder between a part where plastic deformation by thermo plasticitydoes not occur and a part in the plastic-deformable state by thermoplasticity in the position of the discharge orifices 1213 and 1223 ofthe nozzle 12.

In this state, when the nozzle 12 and the predetermined part of theelectric wires 91 are relatively moved, the thermoplastic materialexisting in the nozzle 12 remains inside the thermoplastic materialchannels 1231 and 1241 formed in the first nest member 123 and thesecond nest member 124 by friction between the inner peripheral surfacesof the thermoplastic material channels 1231 and 1241 formed in the firstnest member 123 and the second nest member 124, and the inner peripheralsurfaces of the fitting concave members 1211 and 1221 of the first casebody member 121 and the second case body member 122. On the other hand,the part of the thermoplastic material discharged from the dischargeorifices of the nozzle 12 (the molded covering member 92) is in a statewhere plastic deformation by thermo plasticity does not occur, thereforeit is not plastic-deformed even when it receives a tensile force in theaxial direction. Accordingly, at the discharge orifices of the nozzle 12(i.e., on the border between the deformable part by thermo plasticityand the undeformable part), it is possible to cut the molded coveringmember 92 and the unmolded thermoplastic material without plasticdeformation to pull them out. It is possible to form the border betweenthe thermoplastic-deformable part and the undeformable part in a ringshape by uniformly sending air from the periphery of the covering member92, thus improving the appearance of the cut ends. Accordingly, it ispossible to improve the appearance of the cut end of the covering member92 in the axial direction.

Note that in the wire harness manufacturing method according to theembodiments of the present invention, the heating temperature for thethermoplastic material is low in comparison with the temperature ingeneral injection molding and press molding. Particularly, thetemperature around a lower limit of temperature range where thethermoplastic material is plastic-deformable by thermo plasticity ispreferably applied. Accordingly, it is possible to cool down the moldedcovering member 92 to a temperature at which plastic deformation bythermo plasticity does not occur (or plastic deformation by thermoplasticity is suppressed) even by sending air at a normal temperature.Accordingly, a device to control air temperature (air cooling device) isunnecessary, the structure of the wire harness manufacturing apparatus 1according to the embodiments of the present invention is notcomplicated, and the increment in the number of parts is prevented.Accordingly, an increase of equipment cost is prevented.

Through the above-described processes, the covering member 92 is formedin the predetermined part of the electric wires 91. Note that the samemanufacturing method is applicable to the wire harness manufacturingapparatus according to the second embodiment (in the above description,the nozzle 12 is replaced with the nozzle 22).

The wire harness according to the embodiments of the present invention,the wire harness manufacturing apparatus according to the embodiments ofthe present invention and the wire harness manufacturing methodaccording to the embodiments of the present invention have advantages asfollows.

In the wire harness according to the preferred embodiments of thepresent invention, the reduction of the flexibility of a part in whichthe covering member 92 is molded can be prevented or suppressed.Accordingly, when the wire harness according to the preferredembodiments of present invention is arranged inside a vehicle or thelike, since the predetermined part can be easily deformed, the workingefficiency of the arranging can be improved.

As a part of the inner peripheral surface of the molded covering member92 is attached to the predetermined part of the electric wires 91, themolded covering member 92 is not moved from the predetermined part ofthe electric wires 91. Accordingly, it is unnecessary to fix thecovering member 92 to the electric wires 91 to prevent movement of themolded covering member 92.

Further, the appearance of the wire harness is good in comparison with astructure where a tape as a covering member is wrapped around theelectric wire.

In the wire harness manufacturing apparatus 1 according to the firstembodiment of the present invention, it is possible to prevent orsuppress the rise of equipment cost or reduce the equipment cost.

For example, the nozzle 12 applied to the wire harness manufacturingapparatus 1 according to the first embodiment of the present inventionhas a simple structure and is manufactured at a low cost in comparisonwith an injection mold die. That is, the injection mold die requires astructure to resist pressure of injected thermoplastic material. On theother hand, since no high pressure is applied to the nozzle 12 used thewire harness manufacturing apparatus 1 according to the first embodimentof the present invention, the structure to resist high pressure is notrequired. Accordingly, the nozzle 12 has a simple structure and can bemanufactured in a small size.

Further, in general injection molding, a mold clamping mechanism isrequired so as not to separate upper and lower molds of the molding diedue to the pressure of the injected thermoplastic material. Accordingly,the structure of equipment to form the covering member is complicatedand is expensive. On the other hand, in the wire harness manufacturingapparatus 1 according to the first embodiment of the present invention,even while thermoplastic material is discharged, no force to separateintegrally-connected plural casing members 121, 122 is applied.Accordingly, the wire harness manufacturing apparatus 1 according to thefirst embodiment of the present invention does not require a mechanismcorresponding to the mold clamping mechanism in the equipment forinjection molding.

Further, in general injection molding, it is necessary to apply highpressure to the thermoplastic material to fill thermoplastic material ina mold die. On the other hand, in the structure of the wire harnessmanufacturing apparatus 1 according to the first embodiment of thepresent invention, it is sufficient to merely apply pressure to theplasticized resin material at a level to pass through (flow) thethermoplastic material channels 1212 and 1222 formed in the respectivefirst case body member 121 and the second case body member 122 and thethermoplastic material channels 1231 and 1241 formed in the respectivefirst nest member 123 and the second nest member 124. Accordingly, incomparison with the injection molding, since the pressure applied to thethermoplastic material is low, a small sized device is applicable as adevice to feed the thermoplastic material. Further, a thermoplasticmaterial channel (hose or the like connecting a material plasticizingunit 13 with the nozzle 12) does not require a structure to resist highpressure.

Further, in the structure where the covering member is molded byinjection molding, the size of the molding die is determined incorrespondence with the size of the covering member to be molded.Accordingly, the size of the molding die is increased in accordance withincrement in the size of the covering member to be molded (e.g.,increment in the length in the axial direction). On the other hand, itis possible to set the length in the axial direction of the nozzle 12applied in the wire harness manufacturing apparatus 1 according to thefirst embodiment of the present invention, to a short length, notdepending on the length of the molded covering member 92 in the axialdirection. That is, it is possible to mold a covering member longer thanthe nozzle 12 in the axial direction. Further, it is possible toarbitrarily set the length of the covering member 92 to be molded in theaxial direction.

In this manner, in the wire harness manufacturing apparatus 1 accordingto the first embodiment of the present invention, it is possible toprevent or suppress the equipment cost or delete the equipment cost.

Further, the wire harness manufacturing apparatus 1 according to thefirst embodiment of the present invention has high versatility.

For example, in the structure to form a covering member by injectionmolding, only one type (one size and one shape) of covering member ismolded with a set of mold dies. Accordingly, to form a covering memberin which the thickness changes, it is necessary to prepare mold dies forrespective thicknesses of the covering member. Similarly, to form acovering member in which the axial directional length changes, it isnecessary to prepare mold dies for respective axial directional lengthsof the covering member. On the other hand, the nozzle 12 applied to thewire harness manufacturing apparatus 1 according to the first embodimentof the present invention can change the thickness of the covering memberby controlling the speed of relative movement of the nozzle 12 withrespect to a predetermined part of the electric wire 91 and/orcontrolling the discharge amount of the thermoplastic material per unittime. Accordingly, it is possible with the pair of nozzles 12 to formthe covering member 92 in which the thickness changes. Further, it ispossible to form a covering member in an appropriate length in thepredetermined part of the electric wire 91 by appropriately setting arange of relative movement of the nozzle 12 with respect to thepredetermined part of the electric wire 91.

Accordingly, it is possible with the pair of nozzles 12 to form thecovering member 92 in which the thickness changes.

Further, when the predetermined part of the electric wire 91 has a sizeto be accommodated in the through hole formed with connected plural nestmembers 123, 124, the covering member 92 can be molded regardless of theouter diameter of the predetermined part of the electric wire 91.Accordingly, it is possible to handle the plural sizes of the electricwire (when plural electric wires are included, the diameter of theelectric wire bunch) with the pair of nozzles 12. Further, even when thediameter of the electric wire 91 changes in the middle of the axialdirection, it is possible to integrally mold the covering member 92 overthe diameter-change part without discontinuity (or without nozzle 12change).

On the other hand, the wire harness manufacturing apparatus 2 accordingto the second embodiment of the present invention has the sameadvantages as those of the wire harness manufacturing apparatus 1according to the above-described first embodiment, and advantages asfollows.

In the wire harness manufacturing apparatus 2 according to the secondembodiment of the present invention, the thermoplastic material channels2231 and 2241 are formed in the planar direction of the tabular bodyformed by the connection between the first tabular member 223 (flatplate member 223 a) and the second tabular member 224 (flat plate member224 a). That is, the thermoplastic material channels 2231 and 2241extend in a direction orthogonal to the axial direction of the electricwire passing through the through hole of the tabular body. Accordingly,since the thickness of the nozzle 22 (the size in the axial direction ofthe electric wire) can be reduced, the covering member can be formed toa position closer to the root (branch point or the like) of the electricwire.

This point will be described more particularly with reference to theschematic diagram of FIGS. 18A and 18B. Here a comparison will be madebetween an example as shown in FIG. 18A in which a covering member C isformed on the electric wires W using a nozzle L having a relativelylarge thickness (size in the axial direction of the electric wires W;T1) and an example as shown in FIG. 18B in which the covering member Cis formed on the electric wires W using a nozzle S having a relativelysmall thickness (size in the axial direction of the electric wires W;T2). It is necessary to branch the electric wires W as the subjects ofcoating in the middle as shown in the figures.

When the nozzle L is used, the electric wires W are relatively movedwith respect to the nozzle L (moved downward in FIG. 18A) to form thecovering member C. The electric wires W cannot be relatively moved anymore at a time point of connection between the nozzle L and a branchpoint of the electric wires W. Accordingly, as shown in FIG. 18A, it isimpossible to coat the electric wires W from the branch point of theelectric wires W by about the thickness T1 of the nozzle L.

On the other hand, also when the nozzle S is used, the electric wires Wcannot be relatively moved any more at a time point of connectionbetween the nozzle S and a branch point of the electric wires W.However, as shown in FIG. 18B, the part in which the electric wires Wcannot be coated corresponds to the thickness T2 of the nozzle S fromthe branch point of the electric wire W. That is, in the use of thenozzle S having a relatively small thickness, it is possible to coat theelectric wires W to the position closer to the branch point of theelectric wires W.

That is, in the above-described wire harness manufacturing apparatus 2according to the second embodiment of the present invention, since thenozzle 22 is thinned by forming the thermoplastic material channels 2231and 2241 in the planar direction of the tabular body, when the electricwires are branched, it is possible to coat the electric wires to theposition closer to the branch point.

Further, as described as a modification of the wire harnessmanufacturing apparatus 2 according to the second embodiment, in thethermoplastic material channels 2231 and 2241 branched in pluralchannels, it is possible to set the resistance loss values by lineresistance in the respective channels to approximately uniformizedvalues by increasing the cross-sectional area in accordance withincrement in channel length. That is, it is possible to approximatelyuniformize the pressure values of the thermoplastic material dischargedfrom the discharge orifices 2232 and 2242 in the circumferentialdirection of the electric wire, and therefore the thickness of thecovering member 92 is uniform in the circumferential direction.

According to the wire harness manufacturing method according to theembodiments of the present invention, the order of attaching theconnectors and the like to the ends of the electric wires 91 and moldingthe covering member 92 in the predetermined part of the electric wires91 is not limited.

In the structure where a tubular member (e.g. a corrugate tube) is usedas the covering member and the predetermined part of the electric wiresis accommodated inside the tubular member, the order of attaching theconnectors and the like to the ends of the electric wires and moldingthe covering member may be limited. More particularly, when theconnectors and the like attached to the ends of the electric wires havesizes and shapes which cannot be inserted through the tubular member, itis necessary to insert the electric wires through the tubular memberprior to the attachment of the connectors and the like to the ends ofthe electric wires.

When the order of these processes is limited, a problem as followsoccurs. In the process of attachment of the connectors and the like tothe ends of the electric wires, an automatic device may be used.However, in the state where the electric wires are inserted through thetubular member, it may be impossible to set predetermined electric wiresin the automatic device due to physical interference by the tubularmember and other electric wires. In such case, it is impossible tomanually attach the connectors and the like. As a result, themanufacturing cost of the wire harness is increased, or it is difficultto reduce the manufacturing cost.

On the other hand, in the wire harness manufacturing method according tothe embodiments of the present invention, after the predeterminedconnectors and the like are attached to the ends of the respectiveelectric wire 91, the electric wires 91 are bundled and the coveringmember 92 is molded. Accordingly, the process of attachment of theconnectors and the like to the ends of the electric wires 91 can beperformed in a state where the respective electric wires 91 individuallyexist. Accordingly, in the process of attachment of the connectors andthe like using an automatic device, there is no difficulty in setting ofthe electric wires 91 in the automatic device since there is nointerference by other electric wires 91 and the covering member 92.Accordingly, it is possible to perform the process of attachment of theconnectors and the like to the respective electric wires 91 using anautomatic device and reduce the manufacturing cost.

Note that in the structure where a tube having a slit (tube having anapproximate “C” cross-sectional shape) is used as the covering member,the covering member can be provided in a predetermined part of theelectric wires after the process of attachment of connectors and thelike to the ends of the electric wires. However, in this structure, itis necessary to wrap a tape or the like around the tube to prevent dropof the electric wires from the tube (or to prevent exposure of theelectric wires from opening of the slit). Accordingly the number ofprocess steps is increased. Further, since the tape is required, thenumber of parts is increased. Accordingly, the manufacturing cost isincreased. Further, since the tape is wrapped around the tube, theappearance of the wire harness is bad.

On the other hand, according to the wire harness manufacturing methodaccording to the embodiments of the present invention, the coveringmember 92 without slit can be integrally molded. Since it is notnecessary to wrap a tape around the outer periphery of the coveringmember 92, the number of parts and the number of process steps are notincreased (or the number of parts and the number of process steps can bereduced). Further, since it is not necessary to wrap a tape around thecovering member, the appearance of the wire harness 9 according to theembodiments of the present invention is good.

Further, in the structure using a tube as the covering member, it isnecessary to wrap a tape or the like over the covering member and theelectric wires to prevent shift of the covering member provided in thepredetermined part of the electric wires. Accordingly, the number ofprocess steps is increased (or the number of process steps cannot bereduced). Also, a tape is required, which increases the number of parts.Further, since a tape is wrapped around, the appearance of the wireharness is bad.

On the other hand, in the wire harness manufacturing method according tothe embodiments of the present invention, since a part of the moldedcovering member 92 is attached to the electric wire 91, the coveringmember 92 is not moved from the molded position. Accordingly, it is notnecessary to wrap a tape over the covering member 92 and the electricwires 91. Accordingly, an increase in the number of parts and the numberof process steps can be prevented (or the number of parts and the numberof process steps can be reduced). Further, since it is necessary to wrapa tape around the covering member 92, the appearance of the wire harness9 according to the embodiments of the present invention is good.

Further, according to the wire harness manufacturing method according tothe embodiments of the present invention, it is possible to simply andintegrally mold the covering member 92 having a thickness which changesalong the axial direction (i.e., the covering member in which thestrength differs).

Generally, a covering member having a predetermined function is providedon the electric wires in a predetermined part of a wire harness. Forexample, in a state where the wire harness is provided inside a vehicleor the like, when there is a probability of damage to the electric wiresdue to contact with another member or the like, a protector to guard theelectric wires is provided in that position. As the protector, one ofprotectors having various sizes and hardness levels is appropriatelyprovided in accordance with the level of function of protecting theelectric wires. On the other hand, in a part with a low level ofrequirement for protection of electric wires, a covering member tobundle the electric wires is provided to prevent a state where theelectric wires are unbound. In this covering member, high strength maynot be required. Accordingly, as a structure in the predetermined partof the electric wires, it may be arranged such that a protector isprovided in a position especially requiring protection while a tape iswrapped around the other position. In such structure, since the numberof parts or the wire harness and the number of process steps areincreased, the manufacturing cost is increased, or the manufacturingcost cannot be reduced without difficulty.

On the other hand, according to the wire harness manufacturing methodaccording to the embodiments of the present invention, during molding ofthe covering member 92, it is possible to control the thickness of thecovering member (i.e. the strength) merely by controlling one or both ofthe speed of relative movement between the nozzle 12 and thepredetermined part of the electric wires 91 or the amount ofthermoplastic material discharged from the discharge orifices 1213 and1223 of the nozzle 12 per unit time. That is, it is possible to mold thecovering member 92 having a thickness (strength) which differs along theaxial direction. Accordingly, since it is not necessary to provideplural covering members, it is possible to reduce the number of processsteps. Further, since it is possible to integrally mold the coveringmember 92 having a thickness which changes along the axial directionusing the thermoplastic material, it is possible to reduce the number ofparts of the wire harness.

The embodiments of the present invention have been described in detail.The present invention is not limited to the above embodiments, andvarious changes can be made within a range not departing from thesubject matter of the present invention.

For example, in the wire harness manufacturing method according to theembodiments of the present invention, the cross-sectional shape of thecovering member 92 is an approximate circular shape. However, thecross-sectional shape of the covering member 92 is not limited. Thecross-sectional shape of the covering member 92 may be appropriately setin accordance with the shape and the size of a region where thepredetermined part of the wire harness 9 according to the embodiments ofthe present invention is provided (e.g., a predetermined part inside avehicle such as an automobile). It is possible to appropriately set thecross-sectional shape and size of the covering member 92 byappropriately setting the cross-sectional shape and size of the firstnest member 123 and the second nest member 124.

What is claimed is:
 1. A wire harness manufacturing method comprising:covering an outer periphery of a predetermined part of a single or abundle of a plurality of electric wires, in which a conductor is coatedwith a sheath member, with a covering member, formed by integral moldingin an approximate tubular shape, by heating thermoplastic resin materialto a temperature at which the thermoplastic resin is plastic-deformableand which is lower than a fusing point and discharging the thermoplasticresin material to the outer periphery of the predetermined part from aplurality of directions in a circumferential direction; directlyattaching an inner peripheral surface of the tubular-shaped coveringmember to a part of an outer peripheral surface of the electric wirepositioned outside the bundle of electric wires; and forming a gapbetween the respective electric wires.
 2. A wire harness manufacturingmethod according to claim 1, wherein in formation of the tubular shapecovering member by discharging the thermoplastic resin material to theouter periphery of the bundle of the electric wires, the bundle ofelectric wires is relatively moved in an axial direction of the bundleof electric wires with respect to a discharge part of the thermoplasticresin material.
 3. The wire harness manufacturing method according toclaim 2, wherein a thickness of the tubular shaped covering member ismade to be uniform over an entire length or changed in a middle positionin the axial direction of the electric wire by controlling a dischargeamount of the thermoplastic material per unit time or a speed ofrelative movement of the bundle of electric wires in the axialdirection.
 4. The wire harness manufacturing method according to claim1, further comprising plasticizing the thermoplastic material of thecovering member, discharging the plasticized thermoplastic material tothe outer periphery of the predetermined part of the electric wire, andwherein the inner peripheral surface of the covering member and theouter periphery of the predetermined part of the electric wire areattached by plasticity of the thermoplastic material.
 5. A wire harnessmanufacturing method according to claim 2, further comprising: stoppingrelative movement between the predetermined part of the electric wireand the nozzle and cooling down the molded covering member by sendingair to the covering member from the air blowing unit; and thereafter,cutting the molded covering member and the thermoplastic materialexisting in the nozzle in a position of the thermoplastic materialdischarge orifice of the nozzle and separating the covering member fromthe thermoplastic material, by moving the predetermined part of theelectric wire and the nozzle relatively to each other withoutdischarging the thermoplastic material from the thermoplastic materialdischarge orifice of the nozzle.
 6. The wire harness manufacturingmethod according to claim 1, wherein the thermoplastic resin materialforming the tubular-shaped covering member is polyester hot melt resin.7. A wire harness manufacturing method using the wire harnessmanufacturing apparatus providing a material plasticizing unit thatplasticizes the thermoplastic material to a softened andplastic-deformable state upon reception of an external force,comprising: providing a nozzle that has a through hole, integrallyconnectable and separable into plural parts, which can accommodate thepredetermined part of the electric wire when integrally connected, and athermoplastic material discharge orifice which continuously surrounds anouter peripheral surface of one end of the through hole, comprising:accommodating the predetermined part of the electric wire in the throughhole by integrally connecting the nozzle while holding the predeterminedpart of the electric wire inside; and integrally molding the coveringmember in the approximate tubular shape covering the predetermined partof the electric wire with the thermoplastic material by discharging thethermoplastic material plasticized by the material plasticizing unitfrom the thermoplastic material discharge orifice of the nozzle to theouter periphery of the predetermined part of the electric wire whilemoving the predetermined part of the electric wire and the nozzlerelative to each other, wherein, when the nozzle is integrallyconnected, the covering member that covers the predetermined part of theelectric wire can be integrally molded with the thermoplastic material,by discharging the thermoplastic material, plasticized by the materialplasticizing unit from the thermoplastic material discharge orificeformed in the nozzle, on the outer peripheral surface of thepredetermined part of the electric wire projected from one end of thethrough hole, in a state where the predetermined part of the electricwire is accommodated in the through hole formed in the nozzle.
 8. Thewire harness manufacturing method according to claim 7, wherein thethickness of the covering member is controlled by controlling the speedof relative movement between the predetermined part of the electric wireand the nozzle and/or the amount of the thermoplastic materialdischarged from the thermoplastic material discharge orifice of thenozzle per unit time.